AMC10 2027 - Self-practice Set 1 Question 17

Question 17

Mary chooses a positive two-digit integer. She multiplies it by $3$ and adds $11$, obtaining a two-digit result. Reversing the two digits of that result gives a number from $71$ to $75$, inclusive. What number did Mary choose?

$11$
$12$
$13$
$14$
$15$