A second vaccine must be kept within 3 °C of 5…

A second vaccine must be kept within 3 °C of 5 °C.

Question 79

HardOriginal question

A vaccine must be stored between 2 °C and 8 °C, both included. A fridge's thermometer reads in °F, where $F = \frac{9}{5}C + 32$ .

A second vaccine must be kept within 3 °C of 5 °C. Which inequality states this?

|C - 5| \le 3

Correct answerYour answer

|C - 3| \le 5

Correct answerYour answer

|C + 5| \le 3

Correct answerYour answer

|C - 5| \ge 3

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

"Within 3 of 5" means the distance from 5 is at most 3.
$|C - 5| \le 3$ , that is $2 \le C \le 8$ , the same range as the first vaccine.

Worth noting

$|C - 3| \le 5$ swaps the centre and the allowed distance.

Ten questions from Numerical Inequalities, at your own pace.

Ten questions from Numerical Inequalities, at your own pace.