Question

If $3\le 3t-18\le 18$, then which one of the following is correct?

• A. $15\le 2t+1\le 20$
• B. $8\le t<12$
• C. $8\le t+1\le 13$
• D. $21\le 3t\le 24$
• E. $t\le 7ort\ge 12$

Answer 1

The correct option is C

$8\le t+1\le 13$

Explanation for the correct option:

Finding the given value.

Given,

$3\le 3t–18\le 18$

Adding $\text{'}18\text{'}$both sides

$\Rightarrow$$3+18\le 3t\le 18+18$

$\Rightarrow$ $21\le 3t\le 36$

Dividing $\text{'}3\text{'}$both sides

$\Rightarrow$ $\frac{21}{3}\le \frac{3t}{3}\le \frac{36}{3}$

$\Rightarrow$ $7\le t\le 12$

Adding $\text{'}1\text{'}$both sides

$\Rightarrow$ $8\le t+1\le 13$

Hence, Option ‘C’ is Correct.