Question

The total number of color blocks is 1260. If the ratio of red block to blue block is 2 ∶ 5 and the ratio of blue block to yellow block is 15 ∶ 7, then how many yellow blocks are there?

• A. 315
• B. 675
• C. 745
• D. 270

Answer 1

Answer:

A. 315

Given:

The total number of color block = 1260

The ratio of red and blue is = 2:5

The ratio of blue and yellow is = 15 : 7

Calculation:

Let the yellow color block be X

Multiply by 3 in ratio of red and blue $=(2\times{3})$ :  $(5\times{3})$ = 6 : 15

The ratio of red, blue and yellow color block = 6 : 15 : 7

The number of yellow color blocks $=\frac{7}{6+15+7}\times{1260}$

$=\frac{7}{28}\times{1260}=315$

∴ The required result will be 315.