# Metallic discs of radius 0.75 cm and thickness 0.2 cm are melted to obtain 508.68 cm³ of metal. Find the number of discs melted (use π = 3.14).

**Solution:**

The Volume of one metal disc = πr²h = 3.14 × (0.75)² × (0.2) cm³ = 0.35325cm³

Let the number of metal discs melted = n

n × 0.35325 = 508.68 cm³

n = 508.68/0.35325

n = 1440 metallic discs

1440 metal discs were melted.

**✦ Try This: **Metallic discs of radius 0.75 cm and thickness 0.4 cm are melted to obtain 2289.06 cm³ of metal. Find the number of discs melted (use π = 3.14).

The Volume of one metal disc = πr²h = 3.14 × (1.5)² × (0.4) cm³ = 2.826 cm³

Let the number of metal discs melted = n

n × 2.826 = 2289.06 cm³

n = 2289.06/2.826

n = 810 metallic discs

810 metal discs were melted

**☛ Also Check:** NCERT Solutions for Class 8 Maths Chapter 11

**NCERT Exemplar Class 8 Maths Chapter 11 Problem 107**

## Metallic discs of radius 0.75 cm and thickness 0.2 cm are melted to obtain 508.68 cm³ of metal. Find the number of discs melted (use π = 3.14).

**Summary:**

Metallic discs of radius 1.5 cm and thickness 0.4 cm are melted to obtain 508.68 cm³ of metal. The number of discs melted were 1440

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