What is the valum of 3n+1 when n = 4

13

Step-by-step explanation:

3(4)+1

=12+1

=13

d) 30 units^2

area of rectangle = l × b

we know,

length = 10 unit

breadth = 3 unit

applying the formula,

= l × b

= 10 × 3

= 30 unit^2

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