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A pair of consecutive odd positive integers, both of which are smaller than 19, have a sum that is more than 22. How many such pairs will be there, if we allow a number to be in more than one pair?

Solution

✅ Correct Option: 2

Let the numbers be xx and x+2x+2.

x+x+2>22x+x+2 > 22

2x+2>222x+2 > 22

2x>202x > 20

x>10x > 10

Both numbers are smaller than 19, so x+2<19x+2 < 19, which means x<17x < 17.

Since xx is an odd positive integer, possible values for xx are 11, 13, 15.

The pairs are (11, 13), (13, 15), (15, 17).

Total pairs = 3.

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