Question

If one fifth ball are of black colour and one third ball are of red color and if the total no of balls are 15 dozen find the no of blue balls

Answer 1

Answer:

84 blue balls

Step-by-step explanation:

1 dozen = 12 units

Total number of balls = 15 dozens

15 dozens = 15 × 12

15 dozens = 180 balls

There are 180 balls totally

Number of black balls = 1/5 of the total balls

Number of red balls = 1/3 of the total balls

Number of blue balls = X

Number of black balls = 1/5 × 180

Number of black balls = 36 balls

Number of red balls = 1/3 × 180

Number of red balls = 60 balls

Number of blue balls = total balls - number of black balls + number of blue balls

X = 180 - (60+36)

X = 180 - 96

X = 84

There are 84 blue balls

 

Answer 2

$\sf\underline{Step-by-step \: explanation}$

Given,

Number of total balls = 180

[1 dozen = 12. So, 15 dozen = 15 × 12 which is 180]

To find the number of blue balls, we need to find the number of red and black balls

Number of black balls =

$\tt\dfrac{1}{5}$

So, the number of black balls will be,

Forming an equation,

$\tt\dfrac{1}{5} \: \times \: 180$

After Cancellation...

36

Number of red balls =

$\tt\dfrac{1}{3}$

Forming an equation,

$\tt\dfrac{1}{3} \: \times \: 180$

After Cancellation...

60 Red balls

Number of blue balls,

Black + Red - 180

180 - 36 + 60

180 - 96

84

Hence, the number of blue balls are,

$\huge{\underline{84}}$