Answer:
Jewel is 7 years old
John is 1 year old
Dave is 17 years old
Step-by-step explanation:
From the question we are told that:
Jewel age is 
John age 
Dave's age a Year ago

So that Dave.s age this Year could be

Simplifying Equation for Dave's age we have





Dave is 17 years old
Therefore
Johns age is



John is 1 year old
Answer:
90 bikes.
Step-by-step explanation:
The bike store earns:
(120-80) = 40 dollars per bike sold.
Hence, to break even, the store must sell:
3600/40 = 90 bikes per month.
Hope this helped!
Answer:
Step-by-step explanation:

Answer:
C.15
Step-by-step explanation:
one box has 5 chocolates so 3*5=15