To determine which ratio would result in a valid proportion when set equal to StartFraction 7 over 3 EndFraction, we need to find the ratio that is equivalent to StartFraction 7 over 3 EndFraction.
To do this, we can cross-multiply. When we cross-multiply StartFraction 7 over 3 EndFraction and another ratio, the product of the numerator of StartFraction 7 over 3 EndFraction and the denominator of the other ratio should be equal to the product of the denominator of StartFraction 7 over 3 EndFraction and the numerator of the other ratio.
Let's check each option:
1. StartFraction 9 over 49 EndFraction:
7 x 49 = 343
3 x 9 = 27
These values are not equal, so it is not a valid proportion.
2. StartFraction 18 over 42 EndFraction:
7 x 42 = 294
3 x 18 = 54
These values are not equal, so it is not a valid proportion.
3. StartFraction 42 over 18 EndFraction:
7 x 18 = 126
3 x 42 = 126
These values are equal, so it is a valid proportion.
4. StartFraction 49 over 9 EndFraction:
7 x 9 = 63
3 x 49 = 147
These values are not equal, so it is not a valid proportion.
Therefore, the ratio that results in a valid proportion when set equal to StartFraction 7 over 3 EndFraction is StartFraction 42 over 18 EndFraction.
Hope It Helps :)