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Flora the Florist

Age 14 to 16
ShortChallenge Level Yellow star
Secondary curriculum
  • Problem
  • Solutions

Answer: 6

Using the highest common factor
The number of bunches must divide the number of white roses, the number of yellow roses and the number of red roses.

The highest common factor of $24$, $36$ and $42$ is $6$, so the most bunches Flora can make is $6$, each consisting of $4$ white, $6$ yellow and $7$ red roses.


Using ratio
Use all the roses to make identical bunches - so all bunches will have the same ratio of colours as the total
$24:42:36$
$12:21:18$
$4:7:6$
Cannot simplify further so each bunch has $4$ white roses
So Flora can make $6$ from $24$ white roses


This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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