If on adding 9 to twice of a whole number gives 31, then the whole number is

The whole number is 11.

Step-by-step explanation:

Let's call the whole number x. We can write the following equation:

2x + 9 = 31

Subtracting 9 from both sides of the equation gives us:

2x + 9 - 9 = 31 - 9

2x = 22

Dividing both sides of the equation by 2 gives us:

2x / 2 = 22 / 2

x = 11

(7) 1482 in³

(8) 216 yd³

Step-by-step explanation:

Formulas

Volume of prism

= base × height/length

Area of parallelogram

= base × height

Area of trapezium

= (upper base + lower base) × height ÷ 2

(7)

Area of the base= 19×6

= 114 in²

Length = 13 in

Volume = 144×13

= 1482 in³

(8)

Area of the base= (11+7)×12÷2

= 108 yd²

Length = 2 yd

Volume = 108×2

= 216 yd³