Can you help me with this equation please ??

Question

Y = 100 + 50L + 50K

i have to explain why it's decreasing return to scale and i have no idea .. help me please

Answer 1

Returns to scale means if you double both inputs, what happens to the output?

Let's do an example with L = 10 and K = 10.

Y = 100 + 50*10 + 50*10

   = 100 + 500 + 500

   = 1100

Now double the inputs to L = 20 and K = 20

Y = 100 + 50*20 + 50*20

   = 100 + 1000 + 1000

   = 2100

2100 is less than 2*1100, so this function has decreasing returns to scale.