Question

a publisher sells a book for rs 168 at a profit of 20% face cost of production increases by 30% what should be the increase in the price of the book so that his percentage profit remains the same ??
plz answer my question fast ​

Answer 1

x+x×1/5=168

5x+x/5=168

6x/5=168

Sp1=x=168×5/6=28×5=140

20% value 28 rupees

1%=28/20=1.4 rupee

30%=42

new cp2 is 182 and cp1 was 140

now the profit percentage 20% should be constant so we should consider this 20% for new cp for selling rate

i.e.,

Sp2=182×120/100=182×1.2=218.4

now the increase of the process can be found by Sp2-Sp1=218.4-168=50.4

50.4 is the increased cost may be what is the answer? if this is correct give me a like so that I can understand this is correct