There are 21 persons and there are three languages - French German and Japanese. 10 persons speak German, 12 persons speak Japanese, and 10 persons speak French. 4 can speak only French and 5 can speak only Japanese. 4 can speak French as well as German. 3 persons can speak all languages. How many persons speak Japanese and German?
There are 21 persons and there are three languages - French German and Japanese. 10 persons speak German, 12 persons speak Japanese, and 10 persons speak French. 4 can speak only French and 5 can speak only Japanese. 4 can speak French as well as German. 3 persons can speak all languages. How many persons speak Japanese and German? Correct Answer 5
[ alt="F3 Madhuri Railways 14.04.2022 D1" src="//storage.googleapis.com/tb-img/production/22/04/F3_Madhuri_Railways_14.04.2022_D1.png" style="width: 203px; height: 182px;">
Given
Number of person = 21
Number of persons speak German = 10
Number of persons speak Japanese = 12
Number of persons speak French = 10
Calculation
Let number of person speak French, German and Japanese represents by F, G and J.
French persons = a + b + c + g = 10
Japanese persons = b + d + g + e = 12
German = c + g + e + f = 10
Persons speak all languages, g = 3
persons speak only French, a = 4
Persons speak only Japanese, d = 5
Person speak French and German, (c + g) = 4
c + 3 = 4
⇒ c = 4 - 3
⇒ c = 1
a + b + c + g =,10
⇒ 4 + b + 1 + 3 = 10
⇒ b = 10 - 8
⇒ b = 2
b + d + g + e = 12
⇒ 2 + 5 + 3 + e =12
⇒ e = 12 - 10
⇒ e = 2
persons speak Japanese and German, (g + e) = 3 + 2
⇒ 5
∴ 5 persons speak Japanese and German.