Question

Due to inflation there were two demand increases. After the second increase the price for a certain item became twice as big as the original. By what percent was the first increase, if the second increase was 25%?

Answer 1

Consider, pls, this option:
1) let start price is 'x' and the 1-t increasing is 'y';
2) after the 1-t increasing new1_price is x(y+1);
3) after the 2-d increasing new2_price is 1.25x(y+1);
4) from another side, new2_price is '2x';
5) according to five items it is possible to make up an equation: 1.25x(y+1)=2x; 
1.25(y+1)=2, y=8/5 -1=3/5=0.6.
0.6 means 60%.
Answer: 60%.