8
round each number to the nearest 10, then
640 ÷ 80 = 8 ← estimate
Answer:
Step-by-step explanation:
Answer:
A unit rate is the rate of change in a relationship where the rate is per 1.
The rate of change is the ratio between the x and y (or input and output) values in a relationship. Another term for the rate of change for proportional relationships is the constant of proportionality.
If the rate of change is yx, then so is the constant of proportionality. To simplify things, we set yx=k, where k represents the constant of proportionality.
If you solve a yx=k equation for y, (like this: y=kx), it is called a direct variation equation. In a direct variation equation, y varies directly with x. When x increases or decreases, y also increases or decreases by the same proportion.
To find y in a direct variation equation, multiply x by the constant of proportionality, k.
For example: Given the relationship y=7x, the constant of proportionality k=7, so if x=3, then y=3×7 or 21.
Given the same relationship, if x=7, then y=7×7, or 49.
Step-by-step explanation:
Answer:
the previous population was 62,000.
Step-by-step explanation:
The current population of a city = 83,700
The population of a city has increased by 35% since it was last measured.
We have to calculate the previous population before increasing 35%.
Let the previous population be p
p +(35% × p) = 83,700
p + 0.35p = 83,700
1.35p = 83,700
p =
p = 62,000
Therefore, the previous population was 62,000.
