Question

6400 workers were employed to construct a river bridge in four years. At the end of the first year, 25% workers were retrenched. At the end of the second year, 25% of those working at that time were retrenched. However, to complete the project in time, the number of workers was increased by 25% at the end of the third year. How many workers were working during the fourth year?

Answer 1

Given details are,

Initial number of workers are = 6400

At the end of first year = 25% retrenched

At the end of second year = 25% retrenched

At the end of third year = 25% increased

By using the formula,

A = P (1 + R/100)

x = 6400 (1 – 25/100) (1 – 25/100) (1 + 25/100)

= 6400 (75/100) (75/100) (125/100)

= 6400 (0.75) (0.75) (1.25)

= 4500

∴ Number of workers working during the fourth year is 4500.