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3 years ago

9

How many numbers are equal to the sum of two odd, one digit numbers

1 answer:

Paul [167]3 years ago

5 0

Here is a list of the odd number paired

1+3, 1+5, !+7, and !+9 (there are 4 unique sums - 4, 6,8 and 10)
3+5, 3+7, 3+9 (notice I did not pair 3 with 1 and the the only new sum is 12)
5+7, 5+9 (the only new sum is 14)
7+9 (16 is a new sum)

The sums (no repeats) are 4,6,8,10,12,14 and 16 for a total of seven numbers.

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See explanation

Step-by-step explanation:

1 step:

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2 step:

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3 step:

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