The ratio of yellow blocks to red blocks is 3:5, and the ratio of blue blocks to red blocks is 7:2. What is the ratio of yellow blocks to blue blocks?

Explanation:

The ratio of yellow to red is 3:5. This could mean we have any of the following situations (pick one):

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...

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.

the answer to the question is a  

it has the same slope and the same y-intercept.

1) c 2143.6 cm

2) c 113.0 m

3) a 33.5 ft

4)   d 2 cm

5) c 20 mm

6) 180 in

7) d 120 ft