Answer: 14 cm
Step-by-step explanation:
First take out 1/4 of the pipe, the portion that is white. Then, half of three quarters of the pipe is blue. 1/2 of 3/4 is 3/8. 3/8(blue) + 2/8(white) = 5/8. Thus, 3/8 of the pipe is black. Thus, take 5.25(The length of the black portion) and multiply it by 8/3(reciprocal of 3/8) to get 14.
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