- Gas central heating is used for 5 days, using 102 kWh of energy. If 1 kWh of gas costs 7p, calculate the cost of using the central heating -

Explanation:

Given that,

Gas central heating was used for 5days

At a rate of 102kWh of energy

Then, 1 kWh = 7p

So,

The total time is 5days

t = 5days

1 day = 24hours

Then, t = 5days = 5 × 24 = 120hours

Given 102kWh, then, they consumers 102 kW in one hour, then, for the 120hours,

The total energy used is 102 × 24

Then, total energy = 2448 kWh

So, 1 kWh = 7p,

Then, 2448 kWh = 7 × 2448

2448 kWh = 17,136 p.

So, the cost of the using central heat is 17,136 p

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