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Stage: 4 Challenge Level: Challenge Level:2 Challenge Level:2

The area of the original rectangle was wb.

The area of the altered rectangle is pw x 1.1b.

Since the two areas are equal,

1.1 pwb = wb


1.1 p = 1

so p = 1/1.1 = 10/11
So the width is 10/11 of its original value, so it has been decreased by 1/11, which as a percentage is 9 and 1/11 %, or 9.09 % to 2.d.p.