Mike bought 7 new baseball cards to add to his collection. The next day his dog ate half of his collection. There are now only 41 cards left. How many cards did Mike start with?

Answer: Mike started with 75 cards

Step-by-step explanation:

Hi, to answer this question we have to write an equation:

The number of cards mike started with (x) plus the new cards added (7) must be divided by 2 (since his dog ate half of his collection).

That expression must be equal to the number of cards left (41)

Mathematically speaking:

(x + 7) / 2 = 41

Solving for x:

x+7 = 41x2

x+7 = 82

x = 82-7

x = 75 cards

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