# DAY/DYDD/PÄIVÄ/NAP 10 The Main Challenge

Using seven 7’s (7 7 7 7 7 7 and 7) once each, with + – × ÷ available, it is possible to make various target answers, such as 7 as shown here:

• 7+7+7+7777 = 7,  or perhaps
• 7×(7÷7)×(7÷7)×(7÷7) = 7

In a similar way, show how to make the target answers 1, 2 and 3. The 7puzzle Challenge

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

The 3rd & 4th rows contain the following fourteen numbers:

3   10   13   25   32   35   36   42   44   45   54   60   66   80

What is the sum of the multiples of 4? The Roll3Dice Challenge

From six of the seven groups of numbers below, it is possible to make today’s target number of 10 when each number in the group is used once and + – × ÷ is available:

•   1   1   6
•   1   2   6
•   1   5   5
•   2   2   3
•   2   4   5
•   3   5   5
•   4   5   6

Which is the only group that CANNOT make 10?

The Mathematically Possible Challenge

Using 45 and 10 once each, with + – × ÷ available, which are the only TWO numbers it is possible to make from the list below?

1    4    9    16    25    36    49    64    81    100

#SquareNumbers

The Target Challenge

Can you arrive at 10 by inserting 2, 2, 3 and 5 into the gaps on each line?

•  (◯–◯)×◯×◯ = 10
•  (◯–◯÷◯)×◯ = 10
•  (◯²–◯–◯)÷◯ = 10
•  ◯÷(◯–◯÷◯) = 10   