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Quinna is saving money for a new bike. She has $5.00 in her savings account as of january 1. At the end of each month starting with january 31, she is planning to add to her account and amount that is equal to the amount in the account. determine a method to calculate the amount she adds each monty. Use that method to calculate the amount of money added for each of the first 5 monthsb). Quinn’s needs $400 to purchase the new bike. At the end of which month will she have enough money. Explain your reasoning.

User John McCollum
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1 Answer

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19 votes

At the end of the first month, she has saved $5.00

She is planning to add to her account an amount that is equal to the amount in the account.

a.

If she saved the first month $5.00

The second month she will save 2*$5.00 = $10.00

In the third month, she will save 2*$10.00= $20.00

In the fourth month, she will save 2*$20.00= 40.00

in the fifth month, she will save 2*$40.00 = $80.00

b. Now, we need to continue until the account amount is equal to $400.

Then:

Sixth month 2*$80.00 = $160.00

Seventh month 2*160.00= $320

Eighth month 2*$320 = $640

Hecen, at the end of the eight-month she will have enough money to buy the new bike.

User Bert Verhees
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