Question

Mary collected $2.75 in nickels and dimes. Ten less than twice the number of nickels represents the number of dimes she has. How many of each kind of coin does she have?

Answer 1

Answer: There are 15 nickles and 20 dimes.

Step-by-step explanation:

Since we have given that

Let the number of nickles be 'x'

Let the number of dimes be '2x-10'.

Total amount = $2.75

According to question, we get that

$0.1(2x-10)+0.05x=2.75\\\\0.2x-1+0.05x=2.75\\\\0.25x=2.75+1\\\\0.25x=3.75\\\\x=\dfrac{3.75}{0.25}\\\\x=15$

Hence, there are 15 nickles and $2x-10=2(15)-10=30-10=20$ dimes.

Therefore, there are 15 nickles and 20 dimes.