Here the percentages given as :

C = 40%

as we know, atomic weight of carbon is 12 so, divide 40 by 12 ,weget:

40/12= 3.3

H= 6.60%

Same as the above method ,the atomic mass of hydrogen is 1 so, divide 6.60 by 1

=6.60/1=6.6.

O = 53.53%

th e atomic weight of oxygen is 16

Therefore ,divide 53.35 by 16

53.35/16= 3.3

So here the ratio of compound is 1:2:1

So, the empirical formula is CH2O.

thanks for read.

Hey!

C is 40% ( given.)  40/12=3.3 ( 12 is Atomic weight of carbon)

H is 6.60% (given) 6.6/1=6.6 (1 is Atomic weight of hydrogen)

O is 53.35% (given) 53.34/16=3.3 ( 16 is Atomic weight of oxygen)

the ratios of these compound is 1:2:1

Therefore the empirical formula of compound is CH2O

Hope it helped to clear your delimma.

Thank you.