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# A the more boys the fewer days this is inverse 10 5

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Unformatted text preview: days. This is inverse. 10 · 5 = 15 · x 15x = 50 1 x=3 3 2. 7. (A) Weight times distance from the fulcrum remains constant. 120 · 5 = 100 · x 600 = 100x x = 6 ft. 3. (B) We compare inches to miles. 1 1 3 2= 4 20 x 1 x = 65 2 x = 130 Cross multiply. Multiply by 2. 8. (C) 2 7 1 1 2= 8 4 x 5 15 x= 2 2 5 x = 15 x = 3" Cross multiply. Multiply by 2. 4. (E) We compare dollars to months. 12, 000 x = 5 12 144, 000 = 5 x x = \$28, 800 Cross multiply. 9. 5. (D) We compare pencils to dollars. The cost of n pencils is c dollars. 100 (E) Number of teeth times speed remains constant. 60 · 20 = 40 · x 1200 = 40x x = 30 x n Cross multiply. = c D 100 100 . Multiply by c cx = nD 100 100 nD x= c 10. (C) We compare gallons to square feet. x 1 = 820 150 Cross multiply. 150 x = 820 x = 5.47, which means 6 gallons must be purchased www.petersons.com Percent 5 5. 80 is 40% of what number? (A) 3200 (B) 320 (C) 32 (D) 200 (E) 20 c is 83 % of what number? (A) (B) (C) (D) (E) 1 3 5c 6 6c 5 7c 8 8c 7 2c 3 DIAGNOSTIC TEST Directions: Work out each problem. Circle the letter that appears before your answer. Answers are at the end of the chapter. 1. Write as a fraction: 4.5% (A) (B) (C) (D) (E) 2. Write (A) (B) (C) (D) (E) 3. 9 2 9 20 9 200 9 2000 4.5 10 2 % as a decimal. 5 6. .40 .04 40.0 .004 4.00 1 What is 62 % of 80? 2 (A) 5000 (B) 500 (C) 50 (D) 5 (E) .5 Find 6% of b. (A) .6b (B) .06b (C) (D) (E) b 6 b .06 100 b 6 7. How many sixteenths are there in 87 %? 2 (A) 7 (B) 8 (C) 10 (D) 12 (E) 14 What percent of 40 is 16? (A) (B) (C) (D) (E) 2 1 2 1 4. 8. 25 30 40 45 69 70 Chapter 5 9. Find 112% of 80. (A) 92 (B) 89.6 (C) 88 (D) 70.5 (E) 91 10. What percent of 60 is 72? (A) 105 (B) 125 (C) 120 (D) (E) 83 1 3 110 www.petersons.com Percent 71 1. FRACTIONAL AND DECIMAL EQUIVALENTS OF PERCENTS Percent means “out of 100.” If you understand this concept, it then becomes very easy to change a percent to an equivalent decimal or fraction. Example: 5 , which is equal to .05 100 3.4 34 3.4% means 3.4 out of 100 or , which...
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## This note was uploaded on 08/15/2010 for the course MATH a4d4 taught by Professor Colon during the Spring '10 term at Embry-Riddle FL/AZ.

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