model 3 reducing & exceeding prices Section-Wise Topic Notes With Detailed Explanation And Example Questions

Answer: (d)

Let original price of sugar be Rs. x per kg.

New price= Rs.$({120x}/100) =Rs.({6x}/5)$per kg.

According to the question,

$50/x - 50/{{6x}/5} = 2$

$50/x - {50 × 5}/{6x} = 2$

$50/x - 125/{3x} = 2$

${150 – 125}/{3x} = 2$

$6x = 25 ⇒ x = Rs.25/6$ kg.

Required quantity of sugar = $50/x$

= $50/{25/6} = {50 × 6}/25 = 12$kg.

Answer: (c)

Required percent

= $\text"Decrease%"/{100 - \text"Decrease%"}$ × 100

= $10/{100 - 10} × 100 = 100/9 = 11{1}/9%$

Answer: (b)

The original price of 1 egg = Rs.x

Present price = Rs.$3/2x$

$24/x - 24/{{3x}/2} = 4$

$24/x(1 - 2/3) = 4$

$8/x = 4 ⇒ x = 2$

Present price of eggs per dozen

= $12 × 3/2 × 2 = Rs.36$

Using Rule 31,

New price = ${50 × 24}/{100 × {4/12}}$ = Rs.36

Answer: (d)

Let the original price of sugar = Rs.x /kg.

Reduced price of sugar = 80% of x

= ${x × 80}/100 = Rs.{4x}/5$kg

$36/{{4x}/5} - 36/x = 1/2$

$45/x - 36/x = 1/2$

$9/x = 1/2$ ⇒ x = 9 × 2 = Rs.18/Kg

Using Rule 31,

New price = ${20 × 36}/{100 × 500/100}$ = Rs.14.4

Let the original price be Rs x A.T.Q.

$x - {20x}/100$ = 14.4

${80x}/100$ = 14.4

$x = 144/8$ ⇒ x =18

∴ Original price = Rs.18

Answer: (d)

Let the original price of sugar be Rs.x/kg.

New price = Rs.${9x}/10$ /kg

$270/{{9x}/10} - 270/x =1$

$300/x - 270/x = 1 ⇒ 30/x = 1$ ⇒ x = Rs.30 /kg

Using Rule 31,

New price = ${10 × 270}/{100 × 1}$ = Rs.27

Let the original price be Rs. x

$x - {10x}/100 = 27 ⇒ {90x}/100 = 27$

$x = 2700/90$ ⇒ x = 30

∴ Original price = Rs.30 per kg.

Answer: (c)

Reduced price of 6.2kg of sugar

= 10% of Rs.1116 = Rs.111.6

Reduced price per kg

= Rs.$(111.6/6.2)$ = Rs.18

Using Rule 31,

New price = ${10 × 1116}/{100 × 6.2}$

= $1116/62$ = Rs.18