P = £5,000 is the principal

r = 0.07 or 7% annual rate

m = 4 compounding period per year (compounded quarterly)

i = 0.07/4 interest rate per period

t = 12 years is the time in years

n = t*m = 12*4 = 48 is the total number of compounding periods

A = the future value

The formula for the future value is:

A = P(1 + i)^n

A = 5000(1 + 0.07/4)^48

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click here to see the step by step calculation for A

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A = £42,874.36

The future value in 12 years will be £42,874.36.