3000 + 500 + 60 = 3560
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Your calculator can help you out here if you really have no idea that the exponent of 10 tells you the number of zeros: 10^3 = 1000.
The ratio that represents 20 to 4 is 1/5
Since it is 1 out of 14, take 400 and divide it by 14 (400/14) which would give 28.57142857... . So round to the nearest whole number = 29. SO THE ANSWER IS “C, 29”