C I believe it not so sure
First, "boxes of two sizes" means we can assign variables: Let x = number of large boxes y = number of small boxes "There are 115 boxes in all" means x + y = 115 [eq1] Now, the pounds for each kind of box is: (pounds per box)*(number of boxes) So, pounds for large boxes + pounds for small boxes = 4125 pounds "the truck is carrying a total of 4125 pounds in boxes" (50)*(x) + (25)*(y) = 4125 [eq2] It is important to find two equations so we can solve for two variables. Solve for one of the variables in eq1 then replace (substitute) the expression for that variable in eq2. Let's solve for x: x = 115 - y [from eq1] 50(115-y) + 25y = 4125 [from eq2] 5750 - 50y + 25y = 4125 [distribute] 5750 - 25y = 4125 -25y = -1625 y = 65 [divide both sides by (-25)] There are 65 small boxes. Put that value into either equation (now, which is easier?) to solve for x: x = 115 - y x = 115 - 65 x = 50 There are 50 large boxes.
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Answer: B) 2/3</h3>
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Explanation:
The order is important for ABC and XYZ so we can see what letters pair up.
- A pairs with X since they are the first letters
- B pairs with Y since they are the second letters
- C pairs with Z since they are the third letters
Based on that, we can see that AB pairs with XY as they are the first two letters of ABC and XYZ respectively.
Divide the length XY over AB and reduce
XY/AB = 10/15 = 2/3
We could also divide XZ over AC
XZ/AC = 14/21 = 2/3
and we get the same ratio
