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## 'More Magic Potting Sheds' printed from http://nrich.maths.org/

This problem follows on from

Magic
Potting Sheds
After a year of successful gardening using his magic doubling shed
(introduced in Magic Potting Sheds), Mr McGregor buys a new shed
that trebles the number of plants in it each night. Use the
interactivity to investigate how many plants he needs this time to
get the same number in each garden. What is the smallest number of
plants he could use?

Can you predict how many plants he would need on the first day and
how many he should plant each day if he bought a new shed that
quadruples the number of plants in it each night?

Use the interactivity to test your prediction.

Mr McGregor is so successful that he decides to plant more gardens.
He can still only plant one garden each day.

Use the interactivity to change the number of gardens and
investigate how many plants he should use for each of the different
potting sheds.

What do you find?

Can you find a general rule?

Can you explain why your rule works?

Full Screen
Version
This text is usually replaced by the Flash movie.

Unfortunately, Mr McGregor suffers an attack from evil magic slugs
that eat half of the plants in his (non-magic) potting shed each
night. He still wishes to plant the same number of plants in each
garden.

How many plants does he need on the first day this time, and how
many should he plant each day? (Remember that he can only plant
whole numbers of plants!) Use this interactivity to help you.

Full Screen Version
This text is usually replaced by the Flash movie.