Let 'c' be the number of cones that the coach can buy. Since each ice cream cone costs $2.80, then we have the following expression:
Now, the coach has $42, then we can write the following equation:
To solve for 'c', we just have to move the coefficient 2.8 to the right side doing its opposite operation: division:
therefore, the coach can buy 15 ice cream cones with $42