# Posts by Robo123

Total # Posts: 10

**Binomial Coefficient**

Evaluate: n n-2 (expression should be in large brackets) I got n! /n-2! 2! . I know this is wrong but am not sure what to do next.

**Binomial Coefficients**

Evaulate: n n-2 (expression should be in large brackets) I got n! /n-2! 2! . I know this is wrong but am not sure what to do next.

**Word Problem - Check Answer (geometric Seq)**

1) Suppose five people are ill during the first week of an epidemic and that each person who is ill spreads the disease to four people by the end of the next week. By the end of the tenth week of the epidemic, how many people have been effected by the illness? A - 1477625 b - ...

**Math (sequence)**

Find the first four terms of each sequence. A1= 2 A2=5 An=An-1 + An-2, n≥3

**Geometric series - Check my answer**

What is the first term in a geometric series with ten terms, a common ratio of 0.5 and a sum of 511.5? I got 256 as my answer. 511.5=a1[1-(.5)^10]/1-1/2 511.5=a1(1023/1024)/1/2 511.5=a1(1023/512) ----> divide by both sides 256=a1

**Math - Sum of a Series**

Thanks. Mange to figure it out. Got the same answer as you.

**Math - Sum of a Series**

Find the sum of the series 23 + 18 + 13 + . . .+ (-82) A) -590 B) 590 C) -649 D) 649

**Math - Geometric Series**

Find the sum of the geometric series 128 - 64 + 32 - . . . to 8 terms. a) 85 b) 225 c) 86 d) 85/2 e) not possible

**Math/Pre Cal**

Find the sum of the geometric series 128-64+32-______to 8 terms .

**Math/Pre Cal**

Find the sum of the geometric series 128-64+32-______to 8 terms .