We can use a rule of three simple, direct proportion to solve this problem.
15 pounds correspond to $1.80, then the question is to find the price of one pound, the called unit rate. We state the rule of three:
15 pound ----> $1.80
1 pound -----> x
x = (1)(1.80)/15
x = 0.12
Therefore, each pound costs $0.12 that is the unit rate in pounds
18x can also be expressed as:
= 2x * (4+5)
= 2x * 9
= 18x
ANSWER: 2x * (4 + 5)
Hope this helps! :)
(y - yo) = m.(x - xo)
We have two points (-4, -1) and (1, 4)
(-1 - 4) = m.(-4 - 1)
(-5) = m.(-5)
m = (-5)/(-5)
m = 1
So the slope is 1
Sally paints at a rate of 1/7th room / hour
Steve paints at a rate of 1/6th room / hour
If they both painted together, they would paint 1/7 + 1/6 = 13/42 room/hour
so to paint the whole room, it would take 1/(13/42) = 42/13 =
<u>
3.23 hours (3 significant figures)</u>