﻿ EXERCISES - Sequences and Series - Numbers and Operations - REVIEW OF MAJOR TOPICS - SAT SUBJECT TEST MATH LEVEL 2 ﻿

## PART 2 ## REVIEW OF MAJOR TOPICS ## Numbers and Operations

### 3.4 Sequences and Series ### EXERCISES

1. If a= 3 and a= n + an–1, the sum of the first five terms is

(A)  17

(B)  30

(C)  42

(D)  45

(E)  68

2. If a= 5 and find a3.

(A)  2.623

(B)  2.635

(C)  2.673

(D)  2.799

(E)  3.323

3. If the repeating decimal is written as a fraction in lowest terms, the sum of the numerator and denominator is

(A)  16

(B)  47

(C)  245

(D)  334

(E)  1237

4. The first three terms of a geometric sequence are The fourth term is

(A) (B) (C) (D) (E) 5. By how much does the arithmetic mean between 1 and 25 exceed the positive geometric mean between 1 and 25?

(A)  5

(C)  8

(D)  12.9

(E)  18

6. In a geometric series and . What is r ?

(A) (B) (C) (D) (E) 1. (D) a2 = 5, a3 = 8, a4 = 12, a5 = 17. Therefore, S5 = 45

2. * (D) Press 5 ENTER into your graphing calculator. Then enter and press ENTER twice more to get a3.

3. * (C) The decimal = 0.2 + (0.037 + 0.00037 + 0.0000037 + · · ·), which is 0.2 + an infinite geometric series with a common ratio of 0.01. The sum of the numerator and the denominator is 245.

4. (D) Terms are 31/4, 31/8, 1. Common ratio = 3–1/8. Therefore, the fourth term is 1 · 3–1/8 = 3–1/8 or 5. (C) Arithmetic mean Geometric mean The difference is 8.

(D) Therefore, ﻿

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