# day/dydd 263 at 7puzzleblog.com The Main Challenge

One of our popular Mathelona challenges awaits you; can you complete this by making all four lines work out arithmetically?  Fill the 16 gaps with digits 0 to 9, but each digit can only be inserted a maximum of twice.

◯  +  ◯   =    8    =   ◯  +  ◯
◯  +  ◯   =    8    =   ◯  –  ◯
◯  +  ◯   =    8    =   ◯  ×  ◯
◯  +  ◯   =    7    =   ◯  ÷  ◯ 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 1st & 5th rows contain the following fourteen numbers:

2   6   7   9   14   15   16   21   22   40   50   72   81   84

Which three different numbers listed have a sum of 100? The Factors Challenge

Which of the following numbers are factors of 263?

3     5     7     9     11     13     None of them The Mathematically Possible Challenge

Using 37 and once each, with + – × ÷ available, which are the FOUR numbers it is possible to make from the list below?

4    8    12    16    20    24    28    32    36    40

#4TimesTable The Target Challenge

Can you arrive at 263 by inserting 4, 5, 6, 7 and 8 into the gaps below?

•  (◯×◯×◯)+◯²+◯ = 263   