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# Ft ft 7 inches by 8 mr weiss earned 12000 during the

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Unformatted text preview: d \$12,000 during the first 5 months of the year. If his salary continues at the same rate, what will his annual income be that year? (A) \$60,000 (B) \$28,000 (C) \$27,000 (D) \$30,000 (E) \$28,800 How many pencils can be bought for D dollars if n pencils cost c cents? (A) (B) (C) (D) (E) nD c nD 100c 100 D nc 100 nD c nc 100 D 8. A photograph negative measures 1 2 1 inches. The printed picture is to have its 2 longer dimension be 4 inches. How long should the shorter dimension be? (A) (B) (C) (D) (E) 3 8 1 2" 2 2" 5. 3″ 1 8 3 3" 8 3" www.petersons.com Variation 63 9. A gear with 60 teeth is meshed to a gear with 40 teeth. If the larger gear revolves at 20 revolutions per minute, how many revolutions does the smaller gear make in a minute? 1 (A) 13 3 (B) 3 (C) 300 (D) 120 (E) 30 10. How many gallons of paint must be purchased to paint a room containing 820 square feet of wall space, if one gallon covers 150 square feet? (Any fraction must be rounded up.) (A) 4 (B) 5 (C) 6 (D) 7 (E) 8 www.petersons.com 64 Chapter 4 SOLUTIONS TO PRACTICE EXERCISES Diagnostic Test 1. (B) 2x(4) = 3(x + 5) 8x = 3x + 15 5x = 15 x=3 4 10 = x 20 6. (E) Number of teeth times speed remains constant. 20 · 30 = x · 25 600 = 25x x = 24 2. (E) Cross multiply. 7. 80 = 10x x=8 3. (C) We compare inches to miles. 2 2 =5 25 x 5 (B) Weight times distance from the fulcrum remains constant. 90 · 3 = 50 · x 270 = 50x x=5 2 ft. 5 Cross multiply. 8. 2x = 135 x = 67 4. 1 2 (C) The more dogs, the fewer days. This is inverse variation. 2·3=3·x 6 = 3x x = 2 weeks = 14 days (A) We compare apples to cents. xn = cd dx = nc nc x= d Cross multiply. 9. (D) Number of machines times hours needed remains constant. m ⋅ h = (m – 2) ⋅ x mh x= m–2 5. (B) We compare miles to months. 5 12 = 7000 x 5x = 84,000 x = 16,800 10. (C) The more men, the fewer days. This is inverse variation. 20 · 6 = 24 · x 120 = 24x x=5 The rations will last 1 day less. www.petersons.com Variation 65 Exercise 1 1. (C) 1 ft. 4 in. = 16 in. 1...
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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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