Problem 1: Known Quantities

Angel has 9 nickels and 6 quarters.

To calculate the total number of coins: $\text{Total Coins} = \text{Number of Nickels} + \text{Number of Quarters}$ $\text{Total Coins} = 9 + 6 = 15$

Thus, Angel has 15 coins.

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Problem 2: General Formula for $xx$ nickels and $yy$ quarters

If Angel has $xx$ nickels and $yy$ quarters, the total number of coins can be expressed as: $\text{Total Coins} = xx + yy$

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If you provide specific values for $xx$ and $yy$, we can calculate the exact total. Let me know if you'd like further clarifications or examples!

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Related Questions:

1. How much money does Angel have in dollars if he has 9 nickels and 6 quarters?
2. What is the weight of the coins if a nickel weighs 5g and a quarter weighs 5.67g?
3. If Angel wants to split his coins equally between two people, how many coins does each person get?
4. What percentage of the total coins are nickels?
5. How many dimes would equal the value of 9 nickels and 6 quarters?

Tip: Always double-check units when dealing with mixed quantities like coins to avoid confusion in calculations!