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A board 65 inches long is sawed into two pieces. One of the pieces in 7 inches shorter than twice the length of the other piece. Find the length of the two pieces.

User Zhongjiajie
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1 Answer

16 votes
16 votes

Answer:

24 and 41 inches.

Explanation:

Let the lengths of the two pieces be a and b.

The total length of the two-piece should be the length of the original board.

Therefore:

a + b = 65

One piece, say b, is 7 inches shorter than twice the length of the other, a.

Therefore, we can write the following equation:

b = 2a - 7

The “2a” represents the twice, and the “-7” represents the 7 shorter inches.

We now have a system of equations:

a + b = 65

b = 2a - 7

We can solve using substitution. Substitute the second equation with the first. Hence:

a + (2a - 7) = 65

Combine like terms:

3a - 7 = 65

Add 7 to both sides:

3a = 72

Divide both sides by 3:

a = 24

So, the shorter piece is 24 inches.

Then, we can use our second equation again:

b = 2a - 7

Since we now know a substitute 24 for a and evaluate. Hence:

b = 2(24) - 7

= 48 - 7

= 41

Therefore, the length of the other two pieces is 24 and 41 inches.

User Gluttton
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