PSLE Linda saved $450 in June. This amount was a 10% decrease from what she saved in May. The amount she saved in July was a 10% increase from what she saved in June.
- What was the total amount that Linda saved from May to July?
- What was the percentage decrease in the amount Linda saved in July compared to May?
|
Savings |
May |
100% |
|
Change |
- 10% |
|
June |
90% |
100 u |
Change |
|
+ 10 u |
July |
|
110 u |
(a)
Savings in May = 100%
Savings in June = 100% - 10% = 90%
90% = 450
1% = 450 ÷ 90 = 5
Savings in May
= 100%
= 100 x 5
= $500
Savings in June = 100 u
Savings in July = 100 u + 10 u = 110 u
100 u = 450
1 u = 450 ÷ 100 = 4.5
Savings in July
= 110 u
= 110 x 4.5
= $495
Total savings from May to July
= 500 + 450 + 495
= $1445
(b)
Decrease in savings in July compared to May
= 500 - 495
= $5
Percentage decrease
=
Decrease in savingsSavings in May x 100%
=
5500 x 100%
= 1%
Answer(s): (a) $1445; (b) 1%