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In the game of Power Countdown, you use a set of numbers to make a target number. The only operation you can use is raising something to a power, but you are allowed to use fractional powers - you can use a $3$ to raise a number to the power $3$ or $1\over3$.

Each number can only be used once.You don't have to use all the numbers!

Here is an example:

Countdown: 2,3,4,5,16,32. Target 8.

One way of making the target is:

solution method

Can you find any other ways of making $8$?
Are there any ways which use all the numbers?

Here is another selection.

Countdown: 2,4,5,25,27,81, target 125
How many ways are there to make the target number of $125$?


Below is a selection of numbers and five targets.
Numbers 2,5,16,243,343,512

Targets: 49,89,1024,216,64
How many different ways can you find to make each target?

Are there any targets you can't make? How close can you get?