Question

In the following food chain, 100 J of energy is available to the lion. How much energy was available to the producer? 

Plants → Deer → Lion

Answer 1

You're Answer--

It is given that 100 J of energy is available to lion.  
Let the amount of enrgy available to deer be x Joules. 
According to 10% law,  
10% energy from deer must have been transfered to lion so, energy available to deer can be calculated as, 

  10 100 ×   x   =   100   J T h e r e f o r e ,   x   =  1000   J 

Now, let the amount of enrgy available to plants be y Joules. 
According to 10% law,  
10% energy from plants must have been transfered to deer so, energy available to plant can be calculated as, 
10 100 ×   y   =   1000   J T h e r e f o r e ,   y =  10000   J 

So we have found that energy available to producer is 10,000J.

Hope you understands✌✌

Answer 2

Your answer !!

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100 J of energy is available to the lion !

Let the energy available to deer y

According to 10% law

10 ( 100) ( y ) = 100

y = 1000 J

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Let me energy available to plant be x

Using 10% law

10 ( 100 ) ( x ) = 1000

x = 10000 J

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