To determine the correct value to use for [tex]\( r \)[/tex] in the monthly payment formula [tex]\( M = \frac{P r(1+r)^n}{(1+r)^n - 1} \)[/tex], when the interest rate is given as 6.9%, we need to convert the interest rate from a percentage to a decimal.
1. Start with the given interest rate: 6.9%.
2. Convert the percentage to a decimal by dividing by 100.
[tex]\[
r = \frac{6.9}{100}
\][/tex]
3. Perform the division:
[tex]\[
r = 0.069
\][/tex]
Therefore, the correct value to use for [tex]\( r \)[/tex] in the formula is [tex]\( 0.069 \)[/tex].
Among the provided options, none of them directly match [tex]\( 0.069 \)[/tex]. However, the correct approach to converting a percentage to a decimal is as demonstrated above.
Thus, the accurate value to use for [tex]\( r \)[/tex] given a 6.9% interest rate is [tex]\( 0.069 \)[/tex].
