Answer:
x = 28
Solution:
3/7x = 12
3/7x ÷ 3/7 = 12 ÷ 3/7 ( divide 3/7 in both sides )
x = 12 ÷ 3/7 (divide)
x = 84/3 (simply divide 84 and 3)
x = 28
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(solution for dividing the fraction and the whole number 12 and 3/7, for those who don't know how to divide fractions and whole numbers...)
12/1 ÷ 3/7
12/1 ÷ 7/3 (reciprocal method)
12/1 × 7/3 (change operation to multiplication)
12/1 × 7/3 = 84/3 (multiply)
84/3 ⇒ 28 (simplify)