Simple Interest

Simple Interest (SI)

P×R×T/100

Principal (P)

SI×100/(R×T)

Rate (R%)

SI×100/(P×T)

Time (T)

SI×100/(P×R)

Amount (A)

P+SI

Simple Interest (SI)

A−P

Amount becomes n× Principal, R=?

R=(n−1)×100/T

Amount becomes n× Principal , Time=?

T=(n−1)×100/R

Different rates for different years

Total SI=P(R₁T₁+R₂T₂+R₃T₃+…)/100

Rate₂ (different multipliers)

R₂=((n₂−1)/(n₁−1))×R₁

Time₂ (different multipliers)

T₂=((n₂−1)/(n₁−1))×T₁

SI is n× Principal

RT=n×100

Amount is n× Principal

RT=(n−1)×100

Principal (Different SI, rate & time)

P=(Difference in SI×100)/(Difference in Rate×Difference in Time)

Principal (Amount at two rates)

P=(Difference in Amount×100)/(Change in Rate×Time)

Current Deposit Rate

r=SI×2400/[n(n+1)×Monthly Deposit]

Rate from A₁,A₂,t₁,t₂

R=(A₁−A₂)×100/(A₂T₁−A₁T₂)

Principal from A₁,A₂,t₁,t₂

P=(A₂T₁−A₁T₂)/(T₁−T₂)

Difference of Two SI

(P₂R₂T₂−P₁R₁T₁)/100

Half-yearly SI

Rate=R/2, Time=2T

Quarterly SI

Rate=R/4, Time=4T