UPSC CDS 2 2022 Math Paper

Formula
M1×D1×H1∕W1=M2×D2×H2∕W2
Where, M= Number of men,
D= Number of days, H= Number of hours,
W= Work doneLet, y additional workers are required;
M1=480,D1=10,H1=10,W1=‌

1

4

M2=(480+y),D2=20,H2=8,W2=(1−‌

1

4

)=‌

3

4

Using the above formula
⇒‌

480×10×10

1 4

=‌

(480+y)×20×8

3 4

⇒‌

480×10×10

1

=‌

160(480+y)

3

⇒480+y=900
⇒y=(900−480)=420
∴ The required number of persons is 420.