Question

if mary types at a constant rate and typed 369 words in 7 minutes, how many words can she type in one minute? a student took 24 minutes to complete 16 problems. how many minutes did it take to complete one problem?

Explanation:

First Problem (Mary's Typing):

Step1: Identify the problem type

This is a rate - calculation problem. We know the total number of words typed and the total time taken, and we need to find the number of words typed per minute (the rate). The formula for rate is $rate=\frac{total\ words}{total\ time}$.

Step2: Plug in the values

We are given that Mary typed 364 words in 7 minutes. So we substitute the total number of words ($364$) and the total time ($7$ minutes) into the rate formula.
$rate = \frac{364}{7}$

Step3: Calculate the result

When we divide 364 by 7, we get $364\div7 = 52$.

Second Problem (Student's Problem - assuming the number of problems is 16 as it seems to be a typo, maybe "16 problems" instead of "li problems"):

Step1: Identify the problem type

This is a problem of finding the average time per problem. The formula is $average\ time\ per\ problem=\frac{total\ time}{number\ of\ problems}$.

Step2: Plug in the values

We know the total time is 24 minutes and we assume the number of problems is 16 (to make sense of the problem). So we substitute into the formula: $average\ time\ per\ problem=\frac{24}{16}$

Step3: Calculate the result

Simplifying $\frac{24}{16}$, we can divide both the numerator and the denominator by 8. $\frac{24\div8}{16\div8}=\frac{3}{2}=1.5$ minutes per problem.

Answer:

s:

• Mary can type $\boldsymbol{52}$ words per minute.
• If the student completed 16 problems in 24 minutes, it took $\boldsymbol{1.5}$ minutes to complete one problem.