Ratios & Proportions: Combining Ratios with Different Multipliers - Equate the Common Member
The price ratio of oranges to lemons is $$2{:}3$$. The price ratio of grapefruits to lemons is $$3{:}5$$. What is the ratio, by price, of grapefruit to oranges?
Correct.
Arrange the ratios so that the common member is in the middle. Notice that the grapefruits-to-lemons ratio is reversed to achieve this goal in the representation below:
Oranges : Lemons : Grapefruits
1st ratio ( 2 : 3 ) $$\color{blue}{\times5}$$
2nd ratio ( 5 : 3 ) $$\color{red}{\times3}$$
The lemons are a common quantity to both the given ratios. Equate the number that represents their price by expanding the first ratio by a factor of 5 and expanding the second ratio by a factor of 3.
Oranges : Lemons : Grapefruits
1st ratio ( 10 : 15 )
2nd ratio ( 15 : 9 )
Now, there is one multiplier to the whole __Ratio Box__ and you may combine the ratios. The correct answer is $$9{:}10$$.Incorrect.
[[snippet]]You probably didn't notice that the ratio in this answer choice is in the wrong order. Beware of careless errors.
Incorrect.
[[snippet]]Incorrect.
[[snippet]]Incorrect.
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