Simple Interest Quiz Set 017

We should use the shortcut technique here. If r₁, t₁, r₂, t₂ and r₃, t₃ be the rates and times for three parts with same interest amount, then the three parts must be in the ratio $1/{r_1 t_1} : 1/{r_2 t_2} : 1/{r_3 t_3}$. In our case r₁ = r₂ = r₃ = 10, which cancels, so the ratio is $1/t_1 : 1/t_2 : 1/t_3$. The product of denominators is 11 × 18 × 14 = 2772. Thus, the three parts are in the ratio $252 : 154 : 198$. The parts are: 24160 × $198/{252 + 154 + 198}$, 24160 × $154/{252 + 154 + 198}$ and 24160 × $252/{252 + 154 + 198}$, which are 10080, 6160 and 7920. The smaller is Rs. 6160.

The shortcut formula is P = ${\text"diff" × 100}/{r_1 × t_1 - r_2 × t_2}$. Putting r₁ = 8, t₁ = 22, r₂ = 5, t₂ = 17, diff = 182, we get P = Rs. 200.

The shortcut formula is P = ${\text"diff" × 100}/{r_1 × t_1 - r_2 × t_2}$. Putting r₁ = 11, t₁ = 18, r₂ = 6, t₂ = 16, diff = 816, we get P = Rs. 800.

We should use the shortcut technique here. If r₁, t₁, r₂, t₂ be the rates and times for two parts with same interest amount, then the two parts must be in the ratio $1/{r_1 t_1} : 1/{r_2 t_2}$. In our case r₁ = r₂ = 10, which cancels, so the ratio is $1/t_1 : 1/t_2$. Thus, the two parts are in the ratio $t_2 : t_1$. The parts are: 270 × $2/{1 + 2}$, and 270 × $1/{1 + 2}$, which are 180 and 90. The smaller is Rs. 90.

We should use the shortcut technique here. If r₁, t₁, r₂, t₂ be the rates and times for two parts with same interest amount, then the two parts must be in the ratio $1/{r_1 t_1} : 1/{r_2 t_2}$. In our case r₁ = r₂ = 10, which cancels, so the ratio is $1/t_1 : 1/t_2$. Thus, the two parts are in the ratio $t_2 : t_1$. The parts are: 1100 × $5/{6 + 5}$, and 1100 × $6/{6 + 5}$, which are 500 and 600. The smaller is Rs. 500.