Answer: Elena spent $3.6 +x more than Tammy.
Step-by-step explanation:
Let the cost of each cherry be 'x'.
Cost of watermelon for Elena = $7.75
Cost of 5 pounds of cherries = 5x
So, Equation for Elena would be

Cost of pineapple = $4.15
Number of pounds of cherries = 4
So, Equation for Tammy would be

Now, Elena spent more than Tammy by

Hence, Elena spent $3.6 +x more than Tammy.