A shop has an offer on jumpers as shown below. Buy 4 jumpers and get 1 free!
Kara gets 6 jumpers.
After applying the offer, each one ends up costing £8.50 per jumper.
What is the regular cost of one jumper when not in this offer?

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Step-by-step explanation:

1/10 + 2.5/10 = 3.5/10 of an hour to make one bracelet. Then change to 20ths so the numerator is a whole number.

Divide your time available by the time it takes to make one.                  

                                               21  

                                               4             = 420= 15 bracelets

                                               7                 28

                                              20

10.20 regular cost

Step-by-step explanation:

8.50 x 6 = 51 total

51/5 = 10.20

e^-kt = n/n0 = 0.79  

-kt = ln 0.79  

t = - ln 0.79/0.0001  

= 2357 years

step-by-step explanation: