The Main Challenge
. . . is to arrive at the target number of 18 by adding together five numbers from 1 to 5, which can each be used any number of times in a calculation.
One way of making 18 is 5+5+5+2+1 (or 55521 to save time). Can you list the other EIGHT ways?
The 7puzzle Challenge
The playing board of the 7puzzle game is a 7-by-7 grid of 49 different numbers, ranging from 2 up to 84.
The 3rd & 5th rows contain the following fourteen numbers:
6 7 13 16 21 25 36 42 45 50 66 80 81 84
What is half of the highest prime number on the list?
The Factors Challenge
Which FOUR of the following numbers are NOT factors of 280?
2 4 6 8 10 12 14 16 18 20
The Mathematically Possible Challenge
Using 2, 7 and 10 once each, with + – × ÷ available, which are the only THREE numbers it is possible to make from the list below?
8 16 24 32 40 48 56 64 72 80
#8TimesTable
The Target Challenge
Can you arrive at 280 by inserting 7, 8, 9, 10 and 11 into the gaps below?
- ◯×◯×◯÷(◯–◯) = 280
Answers can be found here.
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