Answer:
Let n represent the number of months after Tina would save the same amount using either option.
400 + 30n = 100 + 50n
400 + 30n − 30n = 100 + 50n − 30n Subtraction Property of Equality
400 = 100 + 20n Combine like terms.
400 − 100=100 + 20n − 100 Subtraction Property of Equality
300 =20n
300
20
=
20n
20
15 months=n
After 15 months, Tina will save the same amount using either option.
400 + 30(15)=100 + 50(15)
400 + 450=100 + 750
850 = 850
After 15 months, Tina will save $850 with either option.
Step-by-step explanation: