44 feet. 3600 seconds. 1 mile
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1 second 1 hour. 5280 feet
I wrote it this way so the units cancel out. You are multiplying the fractions by each other
The car is going 30 mph, and will go 120 miles in 4 hours.
Direct variation is written in the form y = k * x or x = y * k. And, inverse variation is written in the form y = k/x or x = y/k.
For the first problem, if we isolated the y, we would get:
4y = 3x - 1
y = (3/4)x - 1/4
This is written as y = mx + b, which isn’t the form of direct or inverse variation, so the answer is NEITHER.
For the second equation, we could divide by 2 on both sides to isolate x and see if it is in the correct form:
x = 4/y
This is inverse form, so the second question is INVERSE with a constant of variation as 4.
A: We want to select one person who works out three days a week. Our probability is simply 12/80 ~~ 15%
B: At least 4 days a week means 4 days, 5 days, or 6 days.
Hence, we have: (9 + 20 + 8)/80 = 46%
C: At least once a week.
Let's find out how many DO NOT work out and subtract that from our sample space. This means they must work out at least once a week.
(80 - 15)/80 = 81%