Question

A school provides milk to the students daily in a cylindrical glasses of diameter 7 cm. If the glass is filled

with milk upto an height of 12 cm. Find how many litres of milk is needed to serve 1600 students.​

Answer 1

$\LARGE{ \underline{\underline{ \sf{Required \: answer:}}}}$

GiveN:

• Diameter of cylindrical glass = 7 cm.
• Milk was filled upto a height of = 12 cm
• Total no. of glasses served = 1600

To FinD:

• Litres of milk needed to served all the 1600 students?

Step-by-Step Explanation:

First we need to find the volume of milk in the cylindrical glass. Volume of cylinder is calculated by:

$\Large{ \boxed{ \sf{\pi {r}^{2} h}}}$

Where r is the radius and h is the height.

Radius will be : 7/2 cm

Plugging in the given values,

Vol. of 1 glass of milk:

= 22/7 × (7/2)² × 12 cm³

= 22/7 × 7²/4 × 12 cm³

= 22 × 7 × 3 cm³

= 462 cm³

Vol. of 1600 such glasses of milk:

= 462 cm³ × 1600

= 739200 cm³

In litres:

We know that 1 litre = 1000 cm³. Then, 1 cm³ will be equal to 1/1000 l. Then,

⇒ 739200 cm³ = 739200 × 1000 l

⇒ 739200 cm³ = 739.2 litres

Hence,

The total amount of milk in litres needed to serve 1600 students is:

$\huge{ \boxed{ \sf{ \blue{739.2 \: l}}}}$

Answer 2

Answer:

Given :-

• A school provides milk to the students daily in a cylindrical glasses of diameter is 7 cm.
• The glass is filled with upto an height of 12 cm.

To Find :-

• How many litres of milk is needed to serve 1600 students.

Solution :-

Diameter of a cylindrical glasses = 7 cm = $\dfrac{7}{2}$ = 3.5 cm

Height upto the glass filled with milk = 12 cm

Volume of cylindrical glasses = πr²h

⇒ $\dfrac{22}{7}$ × (3.5)² × 12

⇒ $\dfrac{22}{7}$ × 3.5 × 3.5 ×. 12

⇒ $\dfrac{22}{7}$ × $\dfrac{35}{10}$ × $\dfrac{35}{10}$ × 12

⇒ $\dfrac{46200}{10 × 10}$

⇒ 462 cm³

Now, volume of 1 litres glass = 462 cm³

Then, volume of 1600 cylindrical glasses,

⇒ 1600 × 462

⇒ 739200 cm³

Since, 1 litres => 1000 cm²

⇒ 739.2 litres => 739200 cm²

$\therefore$ 739.2 litres of milk is needed to serve 1600 students.