One third of total number of students in a class are in chemistry laboratorry, one fourth are in physics laboratory, one sixth are in biology laboratory and 12 are in mathematics lab. how many students are there in the class?

Asked by ganeshbp18 | 11th Jul, 2014, 07:21: PM

Expert Answer:

L e t space t o t a l space n u m b e r space o f space s t u d e n t s space b e space x. O n e space t h i r d space o f space t o t a l space s t u d e n t s space a r e space i n space c h e m i s t r y space l a b space equals space 1 third left parenthesis x right parenthesis space equals space x over 3 S i m i l a r l y comma space N o space o f space s t u d e n t s space i n space p h y s i c s space l a b space equals space x over 4 N o. space o f space s t u d e n t s space i n space b i o log y space l a b space equals space x over 6 N o. space o f space s t u d e n t s space i n space m a t h s space l a b space equals space 12  N e x t comma T o t a l space n u m b e r space o f space s t u d e n t s space equals space x rightwards double arrow space x over 3 plus x over 4 plus x over 6 space plus space 12 space equals space x space rightwards double arrow space 12 space equals space x space minus space x over 3 minus x over 4 minus x over 6 rightwards double arrow space 12 equals space fraction numerator 12 minus 4 x minus 3 x minus 2 x over denominator 12 end fraction space space space space space space space space space space space space space left parenthesis because space L C M space o f space 3 comma 4 comma 6 space equals space 12 right parenthesis rightwards double arrow space 144 space equals 3 x rightwards double arrow space x space equals space 48 space  H e n c e space t o t a l space n u m b e r space o f space s t u d e n t s space i n space t h e space c l a s s space i s space 48.

Answered by Mili Hariyani | 12th Jul, 2014, 05:55: PM