Given ,A college decide to increase its teacher salary by 30%
But due to corona virus pandemic disease the college later decide to decrease 20% in salary of its employees.
Formula: If x% increase of any value, then Increased value = Actual value
× If y% decrease of any value, then
Decreased value = Actual Value × (100 – x)/100
Calculation: Let salary of the teacher be Rs 100xIncreased salary of the teacher = 100x × (130/100) = 130x
After corona virus salary of the teacher = 130x × (80/100) = 104x
Salary increased by = 104x – 100x = 4x
∴ Salary increased by = (4x/100x) × 100 = 4%
Smart Trick Net increase = x + y + (xy)/
100=30+(−20)+=30−20−6=+4%