Question

The number of campers who sign up for archery each week is listed in the table. If the relationship is proportional, how many campers will sign up for archery in Week 3?

Archery Sign Up Total Campers
Week 1 36 120
Week 2 45 150
Week 3 ? 130

A. 54
B. 40
C. 41
D. 39

Answer 1

A. 54 is your answer

Answer 2

`\boxed{39}`

Explanation:

`\begin{array}{rcc}& \textbf{Archery Sign Up} & \textbf{Total Campers}\\\textbf{Week 1} & 36 & 120\\\textbf{Week 2} & 45 & 150\\\textbf{Week 3} & ? & 130\\\end{array}`

Let x = Total campers

and y = Archery sign up

In a direct proportionality,

y = kx

1. Calculate the value of k

Substitute a pair of values for x and y

150 = k × 45

Divide each side by 45

k = 150/45 = 10/3

2. Calculate the value of x in Week 3

`\begin{array}{rcl}130& = & (10)/(3)x\\\\390 & = & 10x\\x & = & \mathbf{39}\\\end{array}`

`\boxed{\textbf{39 campers}} \text{ will sign up for archery in Week 3}`

The diagram is a graph of your proportionality. It shows that y = 130 when x = 39.