Question

an online seller’s rating went up by 3.3. now the seller’s rating is 5.25. (a) let r be the seller’s rating before it went up. write an equation that can be used to find r. first choose an appropriate form. then fill in the blanks with the letter r and the numbers 3.3 and 5.25. ○ □ + □ = □ ○ □ − □ = □ ○ □ × □ = □ ○ □ ÷ □ = □ (b) solve your equation for r to find the seller’s rating before it went up.

Explanation:

Part (a)

Step1: Analyze the relationship

The seller's previous rating \( r \) increased by 3.3 to become 5.25. So, the previous rating plus the increase equals the current rating.

Step2: Choose the equation form

The appropriate form is addition: \( r + 3.3 = 5.25 \)

Part (b)

Step1: Isolate \( r \)

To solve \( r + 3.3 = 5.25 \), subtract 3.3 from both sides.
\( r + 3.3 - 3.3 = 5.25 - 3.3 \)

Step2: Calculate the result

\( 5.25 - 3.3 = 1.95 \), so \( r = 1.95 \)

Answer:

s:
(a) The equation is \( \boldsymbol{r + 3.3 = 5.25} \) (select the \( \square + \square = \square \) form and fill \( r \), \( 3.3 \), \( 5.25 \))
(b) \( \boldsymbol{1.95} \)