Question

Observe the measures of pots in figure 7.8 and 7.9. How many jugs of water can the cylindrical pot hold ?

Answer 1

In the figure 7.9,

Radius of the cylindrical pot = 7 cm.

Height of the Pot = 10 cm.

∴ Volume of the cylindrical Pot = πr²h

= 22/7 × 7 × 7 × 10

= 220 × 7

= 1540 cm³

Thus, the amount of the water than Cylindrical Pot can holds is 1540 cm³.

From the Figure 7.8,

Radius of the Conical jug = 3.5 cm.

Height of the Jug = 10 cm.

∴ Volume of the water than 1 Jug can holds = 1/3 × 22/7 × 3.5 × 3.5 × 10

= 385/3 cm³.

Now, Number of Jugs of water that is required to fill the cylindrical pot = 1540/(385/3)

= 4 × 3

= 12

Hence, the answer is 12.

Hope it helps.

Answer 2

Hi ,

1 ) Dimensions of the conical jug :

Radius of the jug = r = 3.5 cm

Height ( h ) = 10 cm

volume of the jug = V1 = ( πr²h )/3

2 ) Dimensions of the Cylindrical water pot :

Radius ( R ) = 7 cm

Height ( H ) = 10 cm

Volume of the pot ( V2 ) = πR²H

Let number of jugs of water pot hold = n

n = V2/V1

n = ( πR²H )/( πr²h/3 )

n = ( 3R²H )/( r²h )

n = ( 3 × 7 × 7 × 10 )/( 3.5 × 3.5 × 10 )

n = 12

∴ Number of jugs of water Pot hold = n = 12

I hope this helps you.

: )