Question

karen charges $50 for 3 climbing lessons. at this rate, how much would she charge for 21 lessons?
(a) let a be the unknown amount karen would charge (in dollars). using the values below, create a proportion that can be used to find a.
values:
a
50
3
21
(b) use the proportion from part (a) to find the amount karen would charge for 21 lessons. do not round any computations.
$

Explanation:

Step1: Set up the proportion

We know that the rate is constant, so the proportion of amount to lessons should be equal. So we set up the proportion as $\frac{A}{21}=\frac{50}{3}$.

Step2: Solve for A

Cross - multiply to get $3A = 50\times21$. Then $3A=1050$. Divide both sides by 3: $A=\frac{1050}{3}=350$.

Answer:

350