Ch 5 FDP's

Question 1

Express the following as fractions and simplify

Answer 1

2.45= 2(45/100)= 2(9/20)= 49/20

.008= 8/1000=4/500=2/250=1/125

Question 2

Express the following as fractions and simplify

Answer 2

420%= 420/100=21/5

8%= 8/100= 4/50=2/25

Question 3

Express the following as decimals and simplify

Answer 3

9/2= 9*50=450/ 2*50=100; 450/100= 45/10=4.5

(Dont divide to get decimal. This can lead to error. Instead convert the decimal to fraction in terms to 100 to cancel). This only works if you can convert the den to power of 10. 3,000/10,000=3/10=.3

Question 4

Express the following as decimals and simplify

Answer 4

1(27/4)= 1+6(3/4)= 7.75

(Use this shortcut and memorize the FDP conversion really helps)

12(8/3)= 12+ 2(2/3)= 12= 14.66

Question 5

Express the following as percents

Answer 5

1,000/10= 1,000*10=10,000/10*10=100=10,000/100= 10,000%

25/8= 3(1/8)= 1/8=. 125= 3.125= 312.5%

(Dont divide. Set up mixed fraction and use FDP conversion)

Question 6

Express the following as percents

Answer 6

80.4= 8,040%

.0007=.07%

To convert a decimal to a percent, shift the decimal point 2 places to the right.

Question 7

What number is 62.5% of 192?

Answer 7

This is a percent vs. decimal conversion problem. Recognize that 62.5%=.625/1000=5/8

5/8*192= 5*24= 120