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Bob and John want to buy a gift. If Bob buys it he will $20 short.
If John buys it he will $34 short. If both buy they will $4 short.
What is the cost of gift.
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Let x be the price of the gift, in dollars.
Since Bob is 20 dollars short, he has x-20 dollars;
similarly, John has x-34 dollars.
Altogether, they have (x-20) + (x-34) = 2x-54.
It is exactly x-4 dollars (since altogether they are 4 dollars short)
2x- 54 = x - 4.
From this equation,
x = 54 - 4 = 50.
ANSWER. The gift costs 50 dollars.
Solved.
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It is an entertainment problem - - - THEREFORE, a solution should be in semi-joking form . . .