Dan used 942 units of electricity from July to October

The meter reading in July was 32347 units

a.) work out the meter reading in October
b.) each unit costs 14p so how much does 942 units cost?

step-by-step explanation: 4 cause 2+2=4

below

step-by-step explanation:

1. 5/1

2. 10/16

3. 90/2

4. 1/20

5. 3/1

6. 14/24

7. 1/4

8. 18/10

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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