# Monthly Archives: May 2018

## DAY 152:

The Main Challenge Using the three numbers 1, 2 and 4 just once each, with + – × ÷ available to you, what is the lowest positive number it is NOT possible to make? The 7puzzle Challenge The playing board of the 7puzzle game is a … Continue reading

## DAY 151:

The Main Challenge Solve all four lines arithmetically by replacing the 16 ◯ ‘s below with digits 0-9, but each digit must only be inserted a maximum of TWICE in the whole challenge: ◯ + ◯ = 8 … Continue reading

## DAY 150:

The Main Challenge Find the sum of the numbers that remain after eliminating multiples of 3, 5 and 7 from all the odd numbers between 10 and 40. The 7puzzle Challenge The playing board of the 7puzzle game is a 7-by-7 grid containing 49 … Continue reading

## DAY 149:

The Main Challenge You have been given the task of manually numbering a 100-page document from 1 to 100. How many digits will you write altogether? The 7puzzle Challenge The playing board of the 7puzzle game is a 7-by-7 grid containing 49 … Continue reading

## DAY 148:

The Main Challenge Which is the lowest whole number that is not a multiple of 5, 6, 7, 11 or 13 nor a prime number, square number or cube number? The 7puzzle Challenge The playing board of the 7puzzle game is a … Continue reading

## DAY 147:

The Main Challenge Allocate numerical values to the following fifteen letters in the English alphabet: E=3 F=9 G=6 H=1 I=–4 L=0 N=5 O=–7 R=–6 S=–1 T=2 U=8 V=–3 W=7 X=11 You’ll see that O+N+E=1 and T+W+O=2 and so on, but what … Continue reading

## DAY 146:

The Main Challenge Apart from 987631 (9+8+7+6+3+1), can you find the other FOUR ways you can make 34 when adding together six unique digits from 1-9? The 7puzzle Challenge The playing board of the 7puzzle game is a 7-by-7 grid of 49 different … Continue reading

## DAY 145:

The Main Challenge Lagrange’s Four-Square Theorem states that every integer can be made by adding up to four square numbers. For example, 7 can be made by 2²+1²+1²+1² (4+1+1+1). Show how you can make 31 when using Lagrange’s Theorem in TWO different ways. … Continue reading

## DAY 144:

The Main Challenge Another mini-Mathelona challenge where you must place the eight digits 1, 1, 1, 2, 2, 3, 4 and 5 into the eight gaps so both lines work out arithmetically: ◯ + ◯ = 3 = … Continue reading

## DAY 143:

The Main Challenge Start with the number 50, then: +27 –42 divide by 5 ×4 +50% two-thirds of this ÷7 = ? What is your final answer to this 7-step number trail? The 7puzzle Challenge … Continue reading