Question

x (hours) | y (pages)
1 | 20
3 | 60
4 | 80
5 | 100
according to the values in the table, do x and y have a proportional relationship?
○ yes
○ no
what is the constant of proportionality? write your answer as a whole number or decimal.

Explanation:

Step1: Check proportionality via ratios

Calculate $\frac{y}{x}$ for each pair:
$\frac{20}{1}=20$, $\frac{60}{3}=20$, $\frac{80}{4}=20$, $\frac{100}{5}=20$

Step2: Verify consistent ratio

All $\frac{y}{x}$ equal 20, so proportional.

Step3: Identify constant of proportionality

The constant is the equal ratio value.

Answer:

1. yes
2. 20