At a banquet, the ratio of the number of boys to the number of girls is 5 : 3. 20 boys leave and the ratio becomes 5 : 4. How many girls are at the banquet?

There are 48 girls at the banquet

Step-by-step explanation:

Let the number of boys = x

Let the number of girls=y

Ratio Of boys to girls=5:3

Therefore, x:y=5:3 ... (1)

If 20 boys leave, the ratio becomes 5:4

Sine number of boys=x

If 20 boys leave, new number = x-20

Therefore, x-20:y=5:4 ... (2)

From (1),

3x=5y

From Equation (2),

4 (x-20) = 5y

Therefore: 3x=4x-80

x=80

From (1),

3x=5y

5y=3X80

y=240/5=48

Therefore, there are 48 girls at the banquet