Half of your baseball card collection got wet and was ruined. you bought 9 cards to replace some that were lost. how many did you begin with if you now have 20?

solution:

n/2 + 9 = 20

n/2=20-9

n/2=11

n=22

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step-by-step explanation:

example 2 – simplify: step 1: completely factor both the numerators and denominators of all fractions. step 2: change the division sign to a multiplication sign and flip (or reciprocate) the fraction after the division sign; essential you need to multiply by the reciprocal. step 3 : cancel or reduce the fractions.