Let say that we have 10 Excel cells each one has a number how could we get for example 1250 from the summation of the ten or less cells?

125*10  I S A SIMPLE WAY TO GET1250

You divide1250 by10 (125) to know the number each cell should have. so ensure each cell has a value of125 to get the summation of1250

through if condition if the total of ten cells greater than1250 then display1250 if it is less than1250 then display sum of ten cells.

=IF(SUM(G7:G16)>=1250,1250,SUM(G7:G16)) 

it can be done in many ways i.e. you can divide the the amount1250 in small amounts in such a way that the total of all these amounts must be equal to1250. 

if each cell has value125 the summation will be1250