PSLE
A company offered 100 stand mixers at 10% discount during a 7-day sale. The line graph shows the number of stand mixers left unsold at the end of each day.

1. On which day was the most number of stand mixers sold? Give your answer in this format. (Eg Day 1)
2. What percentage of the 100 stand mixers were sold in the first five days of the sale?
3. During the sale, the discounted price of the stand mixers was $108. After the sale, the remaining stand mixers were sold without discount. What was the total amount of money collected from selling all 100 stand mixers?

(a)
The steepest line is from Day 1 to Day 2.

On Day 2, the most number of stand mixers was sold.

(b)
Number of stand mixers that were left at Day 5 = 35

Number of stand mixers that were sold for the first five days
= 100 - 35
= 65

Percentage of stand mixers that were sold for the first five days
= ⁶⁵₁₀₀ x 100%
= 65%

(c)
Number of stand mixers that were left at the end of the sale = 20

Number of stand mixers that were sold during the sale
= 100 - 20
= 80

Total amount that collected from the stand mixers sold
= 80 x 108
= $8640

Price of each stand mixer after 10% discount 
= 100% - 10%
= 90%

90% of the price = 108
1% of the price = 108 ÷ 90 = 1.2
100% of the price = 100 x 1.2 = 120

Amount collected from selling the remaining stand mixers
= 20 x 120
= $2400

Total amount collected from selling all the 100 stand mixers
= 8640 + 2400
= $11040

Answer(s): (a) Day 2; (b) 65%; (c) $11040