7 Erik has a set of number cards from 1 to 20.
He picks four different cards.
Exactly three of his cards are multiples of 5.
Exactly three of his cards are even numbers.
All four of the numbers add up to less than 40.
What cards could Erik pick?
Answers
Answer:
You may also be interested in our longer problems on Factors, Multiples and Primes.
Printable worksheets containing selections of these problems are available here.
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Age 11 to 14 Short
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Age 11 to 14 Short
Weekly Problem 10 - 2008
If the numbers 1 to 10 are all multiplied together, how many zeros are at the end of the answer?
Factor Trio
Age 11 to 14 Short
Which of the numbers shown is the product of exactly 3 distinct prime factors?
Reversible Primes
Age 11 to 14 Short
How many two-digit primes are there between 10 and 99 which are also prime when reversed?
Multiple Years
Age 11 to 14 Short
Weekly Problem 18 - 2016
The year 2010 is one in which the sum of the digits is a factor of the year itself. What is the next year that has the same property?