CUET Preparation Today
CUET
-- Applied Mathematics - Section B2
Numbers, Quantification and Numerical Applications
If $σ(n)$ = Sum of all positive divisors of n, n ∈ N, then what is the value of $σ(49)$ ?
57
61
63
54
The correct answer is option (1) : 57
$σ(49)$
+ve divisions of 49 are $1, 7, 49$
$∴σ(49)=1+7+49$
$=57$
