Whenever you encounter a quantitative question with answer choices, be sure to SCAN the answer choices before performing any calculations. In many cases, the answer choices provide important clues regarding how to best solve the question.
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Comment on Minimum Number of Marbles
How can I know that 15:12:16
Ratios behave the same way
Ratios behave the same way that fractions do.
So, for example, we know that the fraction 3/7 is in its simplest form, because there are no integers (greater than 1) that will divide into BOTH 3 and 7.
Likewise, we can say that the ratio 3:7 is in simplest terms.
Conversely, we know that the fraction 15/20 is NOT in its simplest form, because 5 will divide into BOTH 15 and 20 to get 3/4
Using the same approach, we know that the ratio 15:12:16 is in simplest terms, since there are no integers (greater than 1) that will divide into 15, 12 and 16
Does that help?
Cheers,
Brent
So this mean that for a
A ratio is expressed in
A ratio is expressed in simplest terms if we cannot find an integer that will divide into ALL of the terms in the ratio.
So, for example, the ratio 30:70:120 is NOT expressed in simplest terms, because we can divide all three terms by 10 to get the EQUIVALENT ratio of 3:7:12
At this point, we know that 3:7:12 IS expressed in simplest terms, because there is no integer that will divide into all three terms.
Likewise, 15:12:16 IS expressed in simplest terms, because there is no integer that will divide into ALL three terms.
Does that help?
Cheers,
Brent