Question

a random sample of students was surveyed and asked to list their grade level and whether or not they have a pet. results are shown in the table below, but some values are missing. fill in the missing values.

pets survey

	pets	no pets	total
7th grade		20	39
8th grade	25	29
total	73		142

Explanation:

Step1: Find the number of 7th - grade students with pets

Using the formula \( \text{Total}=\text{Pets}+\text{No Pets}\). For 7th - grade, if \( \text{Total} = 39\) and \( \text{No Pets}=20\), then \( \text{Pets}=39 - 20\).
\(39-20 = 19\)

Step2: Find the number of 8th - grade students in total

Using the formula \( \text{Total}=\text{Pets}+\text{No Pets}\). For 8th - grade, if \( \text{Pets}=25\) and \( \text{No Pets}=29\), then \( \text{Total}=25 + 29\).
\(25+29=54\)

Step3: Find the total number of students with no pets

Using the formula \( \text{Total}=\text{Pets}+\text{No Pets}\). If \( \text{Total}=142\) and \( \text{Pets}=73\), then \( \text{No Pets}=142 - 73\).
\(142-73 = 69\)

Step4: Find the number of 6th - grade students with no pets

Since the total number of students with no pets is \(69\), and the number of 7th - grade students with no pets is \(20\) and 8th - grade students with no pets is \(29\). Then \( \text{6th - grade No Pets}=69-(20 + 29)\).
\(69-(20 + 29)=69 - 49=20\)

Step5: Find the number of 6th - grade students with pets

Since the total number of students with pets is \(73\), and the number of 7th - grade students with pets is \(19\) and 8th - grade students with pets is \(25\). Then \( \text{6th - grade Pets}=73-(19 + 25)\).
\(73-(19 + 25)=73 - 44 = 29\)

Step6: Find the total number of 6th - grade students

Using the formula \( \text{Total}=\text{Pets}+\text{No Pets}\). For 6th - grade, if \( \text{Pets}=29\) and \( \text{No Pets}=20\), then \( \text{Total}=29+20\).
\(29 + 20=49\)

Answer:

	Pets	No Pets	Total
7th grade	19	20	39
8th grade	25	29	54
Total	73	69	142