Today’s Challenge
There are two rules to consider when calculating the NEXT number in our special sequence:
- if it’s EVEN, halve it
- if it’s ODD, add 1
For example, if starting at 50, the sequence would be:
- 50 25 26 13 14 7 8 4 2 1
So it takes 9 steps to get down from 50 to 1.
Following the above rules, which starting number between 51 and 100 creates the most number of steps (13 steps in all) when eventually arriving at 1?
The 7puzzle Challenge
The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.
The 1st & 3rd rows of the playing board contain the following fourteen numbers:
2 9 13 14 15 22 25 36 40 42 45 66 72 80
Which three numbers, when trebled, are also present on the list?
Make 98 Challenge
Can you arrive at 98 by inserting 2, 4, 5 and 10 into the gaps on each line?
- (◯+◯)×(◯+◯) = 98
- ◯²–◯×(◯–◯) = 98
- ◯³+double(◯+◯+◯) = 98
Answers can be found here.
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