Question

Cut 25 into two pieces in such a way that the first piece is 13 less than the second one. Let x be the second one.

Answer 1

First piece: 6,5

Second piece: 19,5

Explanation:

"Cut 25 into 2 pieces" = "divide 25 by 2"

So, we must divide 25 into 2 unequal pieces, where the first piece is 13 less than the second one (x).

What we could do is simply get a random number, preferably close to 12,5 (the half of 25), and add a number to the first piece and decrease a number from the second one; these two numbers, though, must add to 13 (or any other number you choose) together.

25 / 2 = 12,5

12,5 - 6 = 6,5 (this would be x - 13)

12,5 + 7 = 19,5 (this would be x)

19,5 - 6,5 = 13 or x - (x - 13) = 13 (there is indeed a difference of 13).

Hope it helped,

BiologiaMagister

Answer 2

For this case we propose a system of equations:

x: Variable that represents part number two

y: Variable representing part number one

According to the data we have to:

`x + y = 25\\x = y-13`

Substituting the second equation into the first we have:

`y-13 + y = 252y-13 = 25\\2y = 25 + 13\\2y = 38\\y = \frac {38} {2}\\y = 19`

Thus, the first piece measures 19 units

`x = y-13\\x = 19-13\\x = 6`

Thus, the second measures 6 units

Answer:

`x = 6\\y = 19`