Answer: £1400
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Work Shown:
If you save 40%, then you pay 100% - 40% = 60% of the original price
final price = 60% of original price
final price = 0.60*(original price)
840 = 0.60x
0.60x = 840
x = 840/0.60
x = 1400
The ring was originally £1400 before the discount.