DAY 87

Comment

110 % of 90 %
is 100 % of 90 % plus 10 % of 90 %,
which is 90 % plus ... .

Answer

99 %.

Readers' methods

KLP of Brighton BN3:
90 % of 110 % is nine tenths of 110 %.
One tenth of 110 % is 11 %
so nine times as much is 99 %.

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