Math 20 Math 25 Math Tips davidvs.net # Math 20 Turn In Homework

## Shapeshifting Homework

### Rounding

1. What number is two hundred twelve thousandths?

2. Which is the largest decimal? 0.243, 0.423, 0.324, 0.0423, 0.4023

3. Which is the smallest decimal? 0.243, 0.423, 0.324, 0.0423, 0.4023

4. Round 17,398.967 to the nearest ten.

5. Round 98,807.728 to the nearest tenth.

6. Round 54,498.66118 to the nearest thousand.

7. 2 ÷ 11 = 0.181818... Round that decimal to the nearest thousandth.

8. Alicia's rectangular garden bed has two long sides of length 2.74 meters and two short sides of length 1.22 meters. Estimate the sum of all four sides.

9. Ben's rectangular garden bed has two long sides of length 3.048 meters and two short sides of length 0.9144 meters. Estimate the sum of all four sides.

10. Which garden bed estimate will be closer to the actual sum? How can you know without calculating the actual sums?

After you are very happy with your answers, turn in these Rounding problems here.

### Fraction Format

1. Consider the following six numbers: 315, 1101, 7628, 13025, 110124, and 876. Which are divisible by 3?

2. Consider the following six numbers: 315, 1101, 7628, 13025, 110124, and 876. Which are divisible by 4?

3. How many factors does 126 have?

4. What is the prime factorization of 126?

5. Fully reduce the fraction 16120

6. Change 0.45 to a fraction. Remember to simplify.

7. What is the decimal notation for four-twentieths?

8. The Leaning Tower of Pisa is 184.5 feet tall and leans 13 feet from its base. What is the ratio of the distance it leans to its height?.

9. The area is 0.75 square miles. The population is 35,427 people. What is the unit rate of people per square mile?

10. Brand M soup weighs 54 ounces and costs \$4.79. Brand T soup weighs 59 ounces and costs \$5.99. Which is the better buy?

After you are very happy with your answers, turn in these Fraction Format problems here.

### Percent Format

1. An easy way to divide a number by 1,000 is to scoot the decimal point ___ places to the _____.

2. An easy way to multiply a number by 0.01 is to scoot the decimal point ___ places to the _____.

3. Write 5.5% as a decimal.

4. Write 0.8911 as a percent.

5.Write 0.8% as a fraction.

6. Write 25 38 % as a fraction.

7. Write the fraction 58 as a percent.

8. Write the fraction 1750 as a percent.

9. After we change two-thirds into percent format, do its digits repeat endlessly?

10. Use what you have memorized to write 33 13 percent as a fraction.

After you are very happy with your answers, turn in these Percent Format problems here.

### Measurement

1. 1 foot is how many yards?

2. 7.1 miles is how many feet?

3. 5,280 yards is how many miles?

4. An index card is 0.27 mm thick. What is that thickness in centimeters?

5. An index card is 0.27 mm thick. What is that thickness in meters?

6. A football field is 4,844 cm wide. What is that width in kilometers?

7. 80 ounces is how many pounds?

8.5,200 grams is how many kilograms?

9. One gallon is how many fluid ounces?

10. 806 liters is how many milliliters?

After you are very happy with your answers, turn in these Measurement problems here.

### Fractions

1. A cookie recipe calls for 23 cup of flour. If you are making a double batch, how much flour will you use?

2. What is four-fifths times twenty?

3. What is four-fifths times two-thirds?

4. What is two-thirds divided by three-halves?

5. 2215 ÷ 335 =

6. What is the least common multiple of 12 and 18?

7. What is five-sixths plus three-fourths?

8. What is five-sixths minus three-fourths?

9. A piece of fabric that is 1 34 yards long is cut into seven equal pieces. How long is each piece?

10. Grandma Jorgensen left 23 of her 78 pound silver bullion bar to her son Lloyd. Lloyd gave each of his four children a 14 share. How much silver did each of Lloyd's children receive?

After you are very happy with your answers, turn in these Fractions problems here.

### Percentages

1. What is 25% of 228?

2. What is 40% of 750?

3. The price tag (before sales tax) on an item says \$100. The sales tax rate is 5%. What is the total price (including tax)?

4. During a sale, a dress decreased in price from \$90 to \$72. What was the percent of decrease?

5. An investment increases in value from \$200 to \$216. What is the percent increase?

6. A pinball machine that normall sells for \$3,999 is on sale for \$3,150. What is the rate of discount?

7. Bluebeard has a balance of \$1,834.90 on a credit card with an annual percentage rate of 22.4%. This month's minimum payment is \$36.70. How much less than this minimum payment is the interest? (In other words, if he only pays the minimum payment, how much goes "past" the interest to pay off his principal?)

8. Find the simple interest for a 2 year loan of \$8,000 at a simple interest rate of 12%.

9. Find the simple interest for a 2 month loan of \$8,000 at a simple interest rate of 9.42%.

10. A store takes out a ninety day loan for \$6,500 at 5.25% simple interest. What is the total amount due after ninety days?

After you are very happy with your answers, turn in these Percentages problems here.

### Measurement

1. Two years is how many minutes?

2. A football field is 4,844 cm wide. What is that width in yards? (1 meter ≈ 1.09361 yards)

3. A plane flying 6,500 feet per minute is going about how many miles per hour?

4. Including the end zones, a football field is 360 feet long and 160 feet wide. If you run three laps around a football field, about what percentage of a mile do you run?

5. You want to buy Sculpey III modeling clay online. At amazon.com it costs \$7.29 for 8 ounces. At amazon.co.uk it costs £2.20 for 57 grams. (1 ounce ≈ 28.35 grams. If £1 ≈ \$1.31), which is a better buy?

6. A triangle has base 4 m and height 3.5 m. What is the area?

7. Most billiard tables are twice as long as they are wide. What is the perimeter of a billiard table that measures 4.5 feet by 9 feet?

8. A parallelogram has base 2.3 cm and height 3.5 cm. What is the area?

9. A trapezoid has base 25 cm, top 16 cm, and height 35 cm. What is the area?

10.The standard backyard trampoline has a diameter of 14 feet. What is its area?

After you are very happy with your answers, turn in these Measurement problems here.

## Justice Homework

### Fractions

1. Is the ratio "2.4 to 3.6" proportional to the ratio "1.8 to 2.7"?

2. Solve the proportion: "7 to 1/4" is proportional to "28 to what?"

3. Fifteen hours of studying before a test lets you score 75 points. At that rate, how many points would you expect from studying 18 hours?

4. Julia's car can drive 120 miles on 4.5 gallons of gas. While driving across the country the tank gets down to 0.9 gallons. How many miles are left, for her to find a gas station?

5. Typically 5 people produce 13 kilograms of garbage each day. How many kilograms of garbage are produced each day by the 346,560 people in Lane County?

6. In a class of 40 students, on average six will be left-handed. A certain class has nine left-handed students. How large would you estimate the class is if its proportion of left-handed students is average?

7. A certain dog medicine contains 3/7 of a gram of active ingredient in every 120 gram dose. For a small dog, how much active ingredient is in a 7 gram dose?

8. A 25 pound turkey serves 18 people. How many pounds does each serving weigh?

9. A 25 pound turkey serves 18 people. What is the unit rate of servings per pound?

10. To determine the number of deer in a game preserve, a forest ranger catches, tags, and releases 318 deer. Later he catches 168 deer and sees that 56 of them are tagged. Use a proportion to estimate the number of deer in the game preserve.

After you are very happy with your answers, turn in these Fractions problems here.

### Percentages

1. A number minus 20 equals 120. What is the number?

2. Fifteen times a number equals 3045. What is the number?

3. What percent of 160 is 150?

4. \$39 is what percent of \$50?

5. 56.32 is 64% of what?

6. 80% of what is 16?

7. A salesman earns a 40% commission. One week he earns \$552 in commission. How much did he sell?

8. A student got 35 problems correct on a test with 45 problems. What is his percentage score?

9. A student got 81.7 problems correct on a test (there was partial credit). This scored 86%. How many problems were on the test?

10. A student scored 91% on a test with 40 problems (there was partial credit). How many problems did she get correct?

After you are very happy with your answers, turn in these Percentages problems here.

### Measurement

1. 86 degrees Celsius is what temperature in degrees Fahrenheit?

2. 44 degrees Fahrenheit is what temperature in degrees Celsius?

3. A square with sides 10 feet long has the top quarter removed (like a triangular "bite" taken out of the top). What is the remaining area?

4. A circle of diameter 6 cm has its southwest quarter removed. What is the perimeter of that "Pac-Man" shape?

5. A half-circle window has diameter of 8 feet. What is its perimeter?

6. You want to install a two foot wide sidwalk around a circular swimming pool. The diameter of the pool is 30 feet. What is the area of the donut-shaped sidwalk, rounded to the nearest square foot?

7. Clarabelle's Confusing Pizza Parlor sells a 20 inch diameter pizza for \$18.99, and a 40 cm diameter pizza for \$14.99. Which is the better buy? (1 inch = 2.54 centimeters.)

8. How large a circle (how big an area?) can fit inside a rectangle of base of 12 feet and height of 5 feet?

9. A square is cut in half. The perimeter of the resulting rectangle is 30 feet. What was the area of the original square?

10. The circumference of a quarter is 7.85 cm. What is its area?

After you are very happy with your answers, turn in these Measurement problems here.