Two ratios that are equal to 7:6 are 14:12 and 21:18, as they are the same, but 7 and 6 are multiplied by the same number (2 in the first, and 3 in the second.)
There are two answers:
B) 5
C) 8
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Explanation:
If we had a triangle with sides a, b and c, then we can say
b-a < c < b+a
where b is larger than 'a'. This is the triangle inequality theorem
In this case, a = 5 and b = 9 so,
b-a < c < b+a
9-5 < c < 9+5
4 < c < 14
Telling us that c is some number between 4 and 14, not including either endpoint. If c is a whole number, then c could be any value from this set: {5,6,7,8,9,10,11,12,13}
We see that the numbers 5 and 8 are in this set. The values 3 and 15 are not in the set.