Answer is the ratio 6:35
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Step-by-step explanation:
The ratio of yellow to red is 3:5. This could mean we have any of the following situations (pick one):
- 3 yellow, 5 red
- 6 yellow, 10 red
- 9 yellow, 15 red
and so on. In general, we would have 3x yellow blocks and 5x red blocks. The ratio 3x:5x reduces to 3:5 when dividing both parts by x. The x is some positive whole number. The order is important because yellow must be listed first, then red second.
The same idea applies to the other ratio 7:2, which is the blue to red. In that case, we could have...
- 7 blue, 2 red
- 14 blue, 4 red
- 21 blue, 6 red
- 28 blue, 8 red
- 35 blue, 10 red
- 42 blue, 12 red
and so on. Notice that items in bold (in each list) have "10 red" as part of it. This is directly from the fact we multiply the 5 and 2 to get 5*2 = 10.
So we can connect the two ratios to have: 6 yellow, 10 red, 35 blue.
The ratio of yellow to blue is 6:35. This is the final answer. We cannot reduce this ratio any further due to 6 and 35 having no common factors other than 1. It's the same as saying the fraction 6/35 can't be reduced further.