Question

harita must memorize 90 measures of music for her cello solo at a concert. she plans on memorizing 18 new measures for every 3 days of practice. which equation can be used to determine m, the number of measures harita still needs to memorize, as a function of d, the number of days of practice since she began learning the piece?
o m = 72 - 15d
o m = 90 - 6d
o m = 101 - 21d
o m = 108 - 3d

Explanation:

Step1: Find the number of measures memorized per day

She memorizes 18 measures every 3 days. So per - day memorization is $\frac{18}{3}=6$ measures per day.

Step2: Set up the linear - function formula

The initial number of measures to memorize is $m_0 = 90$. The number of measures memorized after $d$ days is $6d$.
Using the formula $m=m_0-\text{(measures per day)}\times d$.
Substitute $m_0 = 90$ and measures per day $=6$ into the formula, we get $m = 90-6d$.

Answer:

$m = 90 - 6d$ (the second option)