Question

in an examination 53 student passed in physics 52 student passed in chemistry 65 student passed in Biology if 19 student pass in Physics and Chemistry 28student passd in chemistry and biology and 31 student passed in exactly one subject then find total student who passed in physics but not in biology and chemistry​

Answer 1

Answer:

Let M be the percentage of students who passed Math, M=53%

Let P be the percentage of students who passed Physics, P=61%

Let C be the percentage of students who passed Chemistry, C=60%

Let MP be the percentage of students who passed math and physics, MP=24%

Let PC be the percentage of students who passed physics and chemistry, PC=35%

Let MC be the percentage of students who passed math and chemistry, MC=27%

Let N be the percentage of students who passed none, N=5%

The only unknown term is intersection of three that is percentage those who have passed Math, Physics and Chemistry

From the elementary set theory we have:

100% =  N + M + P + C - MP - PC - MC + MPC

100% = 5% + 53% + 61% + 60% - 24% - 35% - 27% + MPC

100% = 93% +MPC

MPC = 100% - 93% = 7%

Now,  in the ratio, the numerator is  MC - MPC = 27% - 7% = 20%;

the denominator is  PC - MPC = 35% - 7% = 28%

Therefore, the ratio is equal to 5/7

Step-by-step explanation: