Please could you help me.. On a Monday, all prices in Isla's shop are 10% more than normal. On Friday all prices in Isla's shop are 10% less than normal. James bought a book on Monday for
£5.50. What would be the price of another copy of this book on Friday?​

£4.50

Step-by-step explanation:

Due to James buying a copy that was £5.50 on a Monday when the prices are 10% more than normal. The original prices would actually therefore be £5.

This means that when the prices are 10% less than normal. The prices would actually be £4.50.

Hope this helps :)

1.0

step-by-step explanation:

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4