The table shows the rates charged for the use of electricity in a country.

1. Brandon and his family used 35 units of electricity in May. How much did they pay for the usage of electricity in May?
2. Nicole and her family paid $130.05 for the usage of electricity in June. How many units of electricity did they use in June?

(a)
Amount that Brandon and his family paid for the usage of electricity
= 35 x 0.84
= $29.40

(b)
Amount that Nicole and her family paid for first 40 units of electricity
= 40 x 0.84
= $33.60

Amount that Nicole and her family paid for next 40 units of electricity
= 40 x 1.53
= $61.20

Amount that Nicole and her family paid for the remaining units of electricity
= 130.05 - 33.60 - 61.20
= $35.25

Remaining units of electricity that Nicole and her family used
= 35.25 ÷ 2.35
= 15

Total number of units of electricity that Nicole and her family used
= 40 + 40 + 15
= 95

Answer(s): (a) $29.40; (b) 95