Rationale
Marci deposited $280.00 in her checking account.
To find out how much Marci deposited, we calculate 7/8 of $320.00, which equals $280.00. This amount represents the portion of the total she chose to deposit.
A) A deposit of $120.00 would represent only 3/8 of the total $320.00, which is significantly less than the 7/8 she deposited. Therefore, this option does not reflect the correct calculation of her deposit.
B) A deposit of $140.00 corresponds to 7/16 of the total amount, which is also less than 7/8. This choice misrepresents the actual fraction of the total that Marci deposited.
C) A deposit of $180.00 is equal to 9/16 of the total $320.00. This amount is still less than 7/8, making it an incorrect option for the portion she deposited.
D) A deposit of $240.00 would be 3/4 of the total $320.00, which, while closer, is still less than the 7/8 that Marci deposited. Thus, this choice does not match the correct calculation.
E) A deposit of $280.00 accurately represents 7/8 of $320.00. This calculation is confirmed by multiplying $320 by 7/8, yielding $280. Thus, this option correctly identifies the amount deposited.
Conclusion
Marci's deposit of $280.00 corresponds to 7/8 of $320.00, accurately reflecting her choice of how much to save. All other options provided either underestimate or miscalculate this fraction of the total amount, reinforcing that the correct answer is indeed $280.00. This illustrates the importance of precise calculations when determining portions of a whole.