PSLE A company offered 100 lamps at 20% discount during a 7-day sale. The line graph shows the number of lamps left unsold at the end of each day.
- On which day was the most number of lamps sold? Give your answer in this format. (Eg Day 1)
- What percentage of the 100 lamps were sold in the first five days of the sale?
- During the sale, the discounted price of the lamps was $16. After the sale, the remaining lamps were sold without discount. What was the total amount of money collected from selling all 100 lamps?
(a)
The steepest line is from Day 1 to Day 2.
On Day
2, the most number of lamps was sold.
(b)
Number of lamps that were left at Day
5 = 30 Number of lamps that were sold for the first five days = 100 - 30 = 70 Percentage of lamps that were sold for the first five days
=
70100 x 100%
= 70%
(c)
Number of lamps that were left at the end of the sale = 5
Number of lamps that were sold during the sale
= 100 - 5
= 95
Total amount that collected from the lamps sold
= 95 x 16
= $1520
Price of each lamp after 20% discount
= 100% - 20%
= 80%
80% of the price = 16
1% of the price = 16 ÷ 80 = 0.2
100% of the price = 100 x 0.2 = 20
Amount collected from selling the remaining lamps
= 5 x 20
= $100
Total amount collected from selling all the 100 lamps
= 1520 + 100
= $1620
Answer(s): (a) Day
2; (b) 70%; (c) $1620