Rounding it to the tens place so your answer for 12mm is going to be 10
To find the area you have to (13.2x18)+(4x4)
To decompose a fraction to one whole, there are different methods to use. The fraction can be decomposed either by division, multiplication(if there are more than one fraction), or addition(if there are more than one fractions).
Example:
Given 8/2, decompose by division:
To do this, divide the numerator by denominator
× =< 11\2
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