Let W = number of white cars, and Y = number of yellow cars.
There were 9 times as many white cars as yellow cars. This means that the number of white cars was 9 times more than the number of yellow cars. This can be translated by the expression:
9Y = W
The person counted 40 cars in total:
W + Y = 40
So we get the system:
In the first equation, we multiply by 9:
9W + 9Y = 360
In the second equation:
9Y= W
W-9Y = 0
Then we add the first with the second equation:
9W + 9Y + W - 9Y = 360
10 W = 360
W = 36
So He counted 36 white cars.
Hope this Helps! :)
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Answer:
a) average rate = (total distance)/(total time)
b) Rave = 2·R1·R2/(R1 +R2)
c) cheetah's average rate ≈ 50.91 mph
Step-by-step explanation:
a) Let AB represent the distance from A to B. Let t1 and t2 represent the travel times (in hours) on leg1 and leg2 of the trip, respectively. Then the distances traveled are...
First leg distance: AB = 70·t1 ⇒ t1 = AB/70
Second leg distance: AB = 40·t2 ⇒ t2 = AB/40
The average rate is the ratio of total distance to total time:
average rate = (AB +AB)/(t1 +t2)
average rate = 2AB/(AB/70 +AB/40) = 2/(1/70 +1/40) = 2(40)(70)/(70+40)
average rate = 560/11 = 50 10/11 . . . mph
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No equations are given, so we cannot compare what we wrote with the given equations. In each step of the solution, we have used the rules of algebra and equality.
b) For two rates over the same distance (as above), the average is their harmonic mean:
average rate = 2r1·r2/(r1+r2)
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c) The cheetah's average rate was 50 10/11 mph ≈ 50.91 mph.
Answer:
Question one = 35a - 15
Question two = 9
Step-by-step explanation:
Distributive property means to multiply all the numbers inside the parenthesis
by the outside number. 5 x 7a equals 35a and 5 x 3 = 15.
35 x 9 - 315 - 15 = 300
A = 9
Answer:
1 piece will cost 2 cents
Step-by-step explanation:
If you divide 7.91 by 0.17, you will get 0.021492, and if you round that up you will get 0.02 which is 2 cents. Now if you want to find the price of more pieces, you can just multiply 2 by however the person needs to buy, and write that as money :)))
Answer:
5
Step-by-step explanation:
<em>G</em><em>CF</em><em> </em><em>=</em><em> </em><em>5</em>