At the 7puzzle company, we produce regular number puzzles for our many followers from over 100 different countries. Our aim is to help improve basic knowledge and confidence of number & arithmetic in a fun way.
Enjoy your visit and spread the message about the fabulous number puzzles at 7puzzleblog.com. Try our latest challenge, #66, which involves inserting arithmetical operations to arrive at the given answer. There are several hundred others at this website.
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Paul Godding, Director of the 7puzzle company
Insert + – x or ÷ where you see each ? below so the answer to the 7-number calculation will equal 80 when working from Left to Right, one step at a time, with no brackets allowed:
6 ? 2 ? 7 ? 7 ? 3 ? 8 ? 5 = 80
A number puzzle with a difference! Your task is to arrive at the target number of 24 by using FOUR unique numbers from 10-19 and with + – × ÷ available to use.
One example is (15 × 12 ÷ 18) + 14 = 24. Can you derive another?
Using 4 unique digits from 1-9, how many different ways can you make 20? As an example, one way is 9+8+2+1. List all the others you can find!
What is the smallest whole number above 200, which when divided by 63, leaves a remainder of nine.
If a=1, b=2, c=3, . . . z=26, find a 7-letter word from the English language that has the value of 80 when the values of the seven letters are added together.
A palindromic number is a number that can be read the same forwards and backwards (e.g. 33 and 797). How many of such numbers are there between 10 and 1,000?
Find the values of eight letters, A to H, from the given information. Each letter contains a different whole number in the range 2-50. Good luck:
- C is an odd number lower than H,
- D is an even number,
- G minus F is either 11 or 12,
- a fifth of B is equal to a third of C,
- F minus D is an odd number,
- H is a third of F, and E is a third of B,
- G divided by five is a whole number and odd,
- D is equal to B minus C,
- A is equal to 150 minus the sum of the other seven numbers.
You have been given a starting number, 18, and must arrive at the same final answer. There are ten arithmetical steps from beginning to end, each involving a whole number. Unfortunately the 9th, and penultimate, step is missing! What should it be?
Start at 18, then:
÷2 +3 –8 ×6 +4 –3 ÷5 ×2 ? ×2 = 18
Starting from 1, find the sum of the first SEVEN whole numbers that do not contain a 3, 5 or 7 as part of their number, or are not multiples of 3, 5 or 7.