PERCENTS ARE RATIOS

PROBLEMS

Do the problem yourself first!

1.   Each percent is what ratio? (What ratio has each percent to 100%?)

Upon studying these, the student will have a "dictionary" which relates percents to ratios. The student should study this dictionary both ways:  From percent to ratio, and from ratio to percent.

 Percent Ratio
 50% Half
 25% A quarter
 75% Three quarters
 12½% An eighth  (Half of a quarter)
 33 13 % A third
 66 23 % Two thirds
 20% A fifth
 40% Two fifths
 60% Three fifths
 80% Four fifths
 10% A tenth
 200% Two times
 300% Three times
 250% Two and a half times
 325% Three and a quarter times
 1000% Ten times
 1% One hundredth
 100% All

2.  a)  A blouse is a blend of cotton and rayon.  It is 72% cotton.  What
2.  a)  percent is rayon?  28%

2.  b)  In a survey, 87½% responded Yes.  What percent responded
2.  a)   No?  12½%

2.  c)  The vote in a recent election was split between candidates A, B,
2.  a)  and C.  Candidate A got 42% of the vote; candidate B got 43%.
2.  a)  What percent did candidate C get?  15%

Mental calculation

3.  The Amount

 3.   a)  12 is 50% of 24. b)  6 is 25% of 24. 3.   c)  18 is 75% of 24. d)  11 is 20% of 55.
 3.   e)  5 is 33 13 % of 15. f)  10 is 66 23 % of 15.
 3.   g)  4 is 12½% of 32. h)  36 is 300% of 12. 3.   i)  500 is 1000% of 50. j)  750 is 250% of 300. 3.   k)  75 is 150% of 50. l)  34 is 425% of 8.

4.  How much is 10% of each of the following?  How much is 1%?

 \$300 \$275 \$50 \$3 \$28 \$5,020 10% \$30 \$27.50 \$5 \$.30 \$2.80 \$502 1% \$3 \$2.75 \$.50 \$.03 \$.28 \$50.20

5.  Calculate mentally from 1%.

 a)  2% of \$300 = \$6.00 b)  3% of \$900 = \$27 c)  5% of \$70 = \$3.50 d)  8% of \$60 = \$4.80 e)  7% of \$4000 = \$280 f)  6% of \$8000 = \$480

6.  The Base

 a)  14 is 50% of 28. b)  8 is 25% of 32.
 c)  9 is 33 13 % of 27 d)  5 is 20% of 25.
 e)  14 is 200% of 7. f)  12 is 300% of 4. g)  10 is 500% of 2. h)  40 is 1000% of 4. i)  \$.25 is 10% of \$2.50. j)  \$.25 is 1% of \$25.

7.  The Percent.  (The question is, Has what ratio?)

 a)  7 is 50% of 14. b)  8 is 33 1/3% of 24. c)  9 is 25% of 36. d)  6 is 20% of 30. e)  12 is 200% of 6. f)  18 is 300% of 6. g)  120 is 1000% of 12. h)  12 is 100% of 12. i)  \$75 is 10% of \$750. j)  \$7.50 is 1% of \$750.

8.  Complete the following.

 8.   a)  12 is 50% of 24. b)  8 is 25% of 32. c)  7 is 20% of 35.
 8.   d)  9 is 33 13 % of 27. e)  12 is 300% of 4. f)  5 is 10% of 50.
 8.   g)  8 is 20% of 40. h)  8 is 1% of 800. i)  3.5 is 1% of 350.

Continue on to the next section.

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