A=2,3,4,5,…,,30
(a,b)=(c,d)⇒ad=bc
(4,3)=(c,d)⇒4d=3c
⇒34=dc
\frac{c}{d}=\frac{4}{3}&c,d\in {2,3,\ldots \ldots ,30}
(c,d)=(4,3),(8,6),(12,9),(16,12),(20,15),(24,18),(28,21)
No. of ordered pair =7
JEE Main 2021 — Mathematics Algebra
Let A=2,3,4,5,….,30 and ′≃′ be an equivalence relation on A×A, defined by (a,b)≃(c,d), if and only if ad=bc. Then the number of ordered pairs which satisfy this equivalence relation with ordered pair (4,3) is equal to :
Held on 16 Mar 2021 · Verified 6 Jul 2026.
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