New SAT Math Workbook

B let x number of 10 cent stamps 40 x number of 15

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: = 210 5. (E) Going Return R 60 50 ·T x x+1 = D 60x 50x + 50 Multiply by 100 to eliminate decimals. 4 x + 5 ( 2 x ) = 21, 000 14 x = 21, 000 x = \$1500 60 x = 50 x + 50 10 x = 50 x=5 If he drove for 5 hours at 60 miles per hour, he drove 300 miles. www.petersons.com 190 Chapter 12 Exercise 1 1. (A) Let x = number of dimes 4 x = number of quarters 10 x = value of dimes in cents 0 100x = value of quarters in cents a Exercise 2 1. (B) Consecutive integers are 1 apart. If the fourth is n + 1, the third is n, the second is n – 1, and the first is n – 2. The sum of these is 4n – 2. (D) The other integer is n + 2. If a difference is positive, the larger quantity must come first. (D) To find the average of any 4 numbers, divide their sum by 4. (C) Represent the integers as x, x + 1, and x + 2. x + x + 2 = 26 2 x = 24 x = 12 x + 1 = 13 2. 3. 4. 10 x + 100 x = 220 100 x = 220 x=2 2. (A) Let x = number of nickels 45 − x = number of dimes 5 x = value of nickels in cents 450 − 10x = value of dimes in cents 5 x + 450 − 10 x = 350 −5 x = −100 x = 20 20 nickels and 25 dimes 3. (B) Let x = number of 10-cent stamps 40 − x = number of 15-cent stamps 10 x = value of 10-cent stamps 600 − 15 x = value of 15-cent stamps 5. (C) An even integer follows an odd integer, so simply add 1. 10 x + 600 − 15 x = 540 −5 x = −60 x = 12 4. (C) Let x = number of nickels 30 − x = number of quarters 5 x = value of nickels in cents 750 − 25 x = value of quarters in cents 5 x + 750 − 25 x = 470 −20 x = −280 x = 14 5. (C) Let 3x = number of nickels 4 x = number of dimes 3x + 4 x = 28 7 x = 28 x=4 There are 16 dimes, worth \$1.60. www.petersons.com Problem Solving in Algebra 191 Exercise 3 1. (C) Let x = Stephen's age now 4 x = Mark's age now x + 1 = Stephen's age in 1 year 4 x + 1 = Mark's age in 1 year 4 x + 1 = 3( x + 1) 4 x + 1 = 3x + 3 x=2 Exercise 4 1. 2. 3. (B) She invested x + 400 dollars at 5%. The income is .05(x + 400). (E) He invested 10,000 – x dollars at 5%. The income i...
View Full Document

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.

Ask a homework question - tutors are online