Percentage Increase and Decrease

Calculate the percentage increase if a value goes from 50 to 70.

• 30%

• 60%

• 25%

• 40%

Answer explanation

To calculate the percentage increase, subtract the original value from the new value (70-50=20), then divide the result by the original value (20/50=0.4), finally multiply by 100 to get the percentage (0.4*100=40%). Therefore, the percentage increase is 40%.

Tags

CCSS.6.RP.A.3C

Find the percentage decrease if a value decreases from 80 to 60.

• 20%

• 25%

• 15%

• 30%

Answer explanation

To find the percentage decrease, calculate the difference between the initial value (80) and the final value (60), which is 20. Then, divide the difference by the initial value (80) and multiply by 100 to get 20% decrease.

Tags

CCSS.6.RP.A.3C

If a value increases by 25%, what is the original value if the new value is 125?

• 75

• 150

• 100

• 110

Answer explanation

To find the original value, we need to divide the new value by 1.25 (1 + 25%). 125 / 1.25 = 100. Therefore, the original value is 100.

Tags

CCSS.6.RP.A.3C

A value decreases by 40%, what is the original value if the new value is 60?

• 120

• 100

• 50

• 80

Answer explanation

To find the original value, we need to reverse the 40% decrease from the new value. If the new value is 60, the original value is 100 (60 / 0.6). Therefore, the correct answer is 100.

Tags

CCSS.6.RP.A.3C

If the rate is 3:5, express it as a percentage.

• 50% : 50%

• 40% : 60%

• 25% : 75%

• 37.5% : 62.5%

Answer explanation

To express the rate 3:5 as a percentage, divide each part by the total (3+5=8) and multiply by 100. This gives 37.5% and 62.5%, which is the correct choice.

Add 1/4 and 1/3, and express the result as a fraction.

• 9/16

• 7/12

• 2/7

• 5/12

Answer explanation

To add 1/4 and 1/3, find a common denominator which is 12. Then, convert both fractions to have the denominator of 12. 1/4 becomes 3/12 and 1/3 becomes 4/12. Adding them gives 7/12.

Tags

CCSS.7.NS.A.1C

Convert 0.75 to a fraction.

• 3/4

• 1/2

• 4/5

• 2/3

Answer explanation

To convert 0.75 to a fraction, we can write it as 75/100 and simplify by dividing both the numerator and denominator by 25 to get 3/4, which is the correct choice.

What is 60% of 80?

• 48

• 70

• 36

• 52

Answer explanation

To find 60% of 80, you multiply 80 by 0.60. 80 * 0.60 = 48. Therefore, 60% of 80 is 48.

Tags

CCSS.6.RP.A.3C

If an item costs $20 for 2 units and $30 for 3 units, which is the better buy?

• The $30 for 3 units is the better buy

• The $20 for 2 units is the better buy

• Both options are equally good buys.

• It depends on the quality of the item

Answer explanation

Both options are equally good buys because the cost per unit is the same for both options ($10 per unit).

Tags

CCSS.6.RP.A.3B

Convert 0.6 to a percentage.

• 50%

• 60%

• 80%

• 75%

Answer explanation

To convert a decimal to a percentage, multiply by 100. 0.6 * 100 = 60%, so the correct answer is 60%.