यदि `(7 xx 8)/9 =3, (8 xx 9)/144 = 12, (10 xx 11)/169 =13`, तो `(12 xx 13)/441=?`

Options

A. 196
B. 225
C. 144
D. 21

Answer

D

Explanation

`(7 xx 8)/9 =3`
`rArr sqrt(9)=3`
`=(8 xx 9)/144=12`
`rArr sqrt(144)=12`
`(10 xx 11)/169 =13`
`rArr sqrt(169)=13`
अतः `(12 xx 13)/441 rArr sqrt(441)=21`