DAY 169:

Today’s Challenge

Three unique digits from 1-9 must be used to arrive at a specified target number. This is done by multiplying two of these numbers together and either adding or subtracting the third unique number to arrive at your target. Today’s target number is 18.

By using the formula (a×b)±c, where a b and c are three unique digits from 1-9, one way of arriving at 18 is (5×4)2.  Find the other FOUR ways it is possible to make 18.

[Note:  (5×4)–2 = 18 and (4×5)2 = 18  counts as just ONE way.]

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid of 49 different numbers, ranging from up to 84.

The 2nd & 7th rows contain the following fourteen numbers:

4    8    11    17    24    27    28    30    48    55    63    64    70    77

Which number above 20 becomes a multiple of 11 when 20 is subtracted from it?

Make 169 Challenge

Can you arrive at 169 by inserting 10, 11, 12 and 13 into the gaps below?

◯×(◯+◯–◯) = 169

Answers can be found here.

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