PSLE Linda spent $700 in June. This amount was a 30% decrease from what she spent in May. The amount she spent in July was a 30% increase from what she spent in June.
- What was the total amount that Linda spent from May to July?
- What was the percentage decrease in the amount Linda spent in July compared to May?
|
Spending |
May |
100% |
|
Change |
- 30% |
|
June |
70% |
100 u |
Change |
|
+ 30 u |
July |
|
130 u |
(a)
Spending in May = 100%
Spending in June = 100% - 30% = 70%
70% = 700
1% = 700 ÷ 70 = 10
Spending in May
= 100%
= 100 x 10
= $1000
Spending in June = 100 u
Spending in July = 100 u + 30 u = 130 u
100 u = 700
1 u = 700 ÷ 100 = 7
Spending in July
= 130 u
= 130 x 7
= $910
Total spending from May to July
= 1000 + 700 + 910
= $2610
(b)
Decrease in spending in July compared to May
= 1000 - 910
= $90
Percentage decrease
=
Decrease in spendingSpending in May x 100%
=
901000 x 100%
= 9%
Answer(s): (a) $2610; (b) 9%