In an examination, 50%examinees got grade 'A' in mathematics, 75% got grade 'A' in Science, and 35 students got grade 'A' in both the subject. If none of them got other than grade 'A' in both subjects 1.represent the above information in a Venn diagram
2.Find the number of examinees who got grade 'A' in Science only​

15

Step-by-step explanation:

yes it is subtracting by 75-35 then we got the answer who got A in the science only

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4