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zafar has 13 coins. coins consist of 5 or 10 cents. how many cents zafar has in total.
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If Zafar has one 5-cent coin and twelve 10-cent coins, can you answer how many cents does he have? I am sure you can.
If Zafar has two 5-cent coins and eleven 10-cent coins, can you answer how many cents does he have? I am sure you can.
If Zafar has three 5-cent coins and ten 10-cent coins, can you answer how many cents does he have? I am sure you can.
If you can answer the first three questions, you can solve the problem to the end.