Let A={1,3,4,6,9} and B={2,4,5,8,10}. Let R be a relation defined on A×B | Sets & Relations | Maths

Let A={1,3,4,6,9} and B={2,4,5,8,10}. Let R be a relation defined on A×B such that R={((a1, b1),(a2,b2)):a1 less than or equal to b2 and b1 less than or equal to a2}. Then the number of elements in the set R is:
A. 180
B. 26
C. 52
D. 160

[ArtiPandey-jy]

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