The table shows the rates charged for the use of utility in a country.
- Gabriel and his family used 25 units of utility in January. How much did they pay for the usage of utility in January?
- Rachel and her family paid $139.80 for the usage of utility in February. How many units of utility did they use in February?
(a)
Amount that Gabriel and his family paid for the usage of utility
= 25 x 0.87
= $21.75
(b)
Amount that Rachel and her family paid for first 30 units of utility
= 30 x 0.87
= $26.10
Amount that Rachel and her family paid for next 30 units of utility
= 30 x 1.36
= $40.80
Amount that Rachel and her family paid for the remaining units of utility
= 139.80 - 26.10 - 40.80
= $72.90
Remaining units of utility that Rachel and her family used
= 72.90 ÷ 2.43
= 30
Total number of units of utility that Rachel and her family used
= 30 + 30 + 30
= 90
Answer(s): (a) $21.75; (b) 90