Which statement describes the sequence {1,3,7,15, ...} as a mathematical statement?

A The nth value equals 1 more than the sum of the previous value and n.

B The nth value equals 1 more than twice the previous value.

C The nth value equals the sum of the previous 3 values.

D The nth value equals 1 more than twice the first value.

Question

Jamal Walter

Mathematics

28 April, 01:27

Which statement describes the sequence {1,3,7,15, ...} as a mathematical statement?

A The nth value equals 1 more than the sum of the previous value and n.

B The nth value equals 1 more than twice the previous value.

C The nth value equals the sum of the previous 3 values.

D The nth value equals 1 more than twice the first value.

+3

Answers (1)

Know the Answer?

Adrienne Pugh · Answer 1

The answer is

B. The nth value equals 1 more than twice the previous value.

Look at the 2nd value, which is 3.

The previous value is 1. Twice of 1 is 2; add one more gets you 3.

Look at the 3rd value, which is 7.

Previous value to 7 is 3. Twice of 3 is 6; add one more gets you 7.

Look at the 4th value, which is 15.

Previous value to 15 is 7. Twice of 7 is 14; add one more gets you 15.

This pattern holds.