It takes 10 years for a $100 monthly bank deposit to amount to $15,528.23 when invested at 5% interest compounded monthly. Round to the nearest place value, then express the amount $15,528.23 in the form of a×10^n

where a
is single digit..

1 answer

To express the amount $15,528.23 in the form of \( a \times 10^n \), where \( a \) is a single digit, we first write the number in scientific notation.

  1. Identify the single digit coefficient \( a \):

    • The amount is $15,528.23.
    • We can rewrite it as \( 1.552823 \times 10^4 \) because moving the decimal point 4 places to the left makes it become 1.552823.
  2. Round \( a \) to one significant figure:

    • Rounding \( 1.552823 \) to one significant figure gives us \( 2 \) (since the first digit after 1 is 5, we round up).
  3. Determine \( n \):

    • From our previous step, we moved the decimal point 4 places to the left, so \( n = 4 \).

Putting it all together, we have: \[ 15,528.23 \approx 2 \times 10^4 \]

Thus, the final answer is: \[ \boxed{2 \times 10^4} \]