Question

William is thinking of a number n, and he wants his sister to guess the number. His first clue is that five less than two times his number is between negative three and fifteen. Write a compound inequality that shows the range of numbers that William might be thinking of.

Answer 1

Answer:

See explanation

Step-by-step explanation:

William is thinking of a number n.

Then

two times his number = 2n

five less than two times his number = 2n - 5

The result is between negative three and fifteen, so

$-3\le 2n-5\le 15$

Solve this compound inequality. First, add 5:

$-3+5\le 2n-5+5\le 15+5\\ \\2\le 2n\le 20$

Divide it by 2:

$1\le n\le 10$

William's number is between 1 and 10