Question

A shopkeeper earns a profit of Re 1 by selling one pen and incurs a loss of 40 paise
per pencil while selling pencils of her old stock.
(i) In a particular month she incurs a loss of Rs 5. In this period, she sold 45 pens.
How many pencils did she sell in this period?
(ii) In the next month she earns neither profit nor loss. If she sold 70 pens, how many
pencils did she sell?
2. In a class test (+ 3) marks are given for every correct answer and (–2) marks are given
for every incorrect answer and no marks for not attempting any question.
(i) Radhika scored 20 marks. If she has got 12 correct answers, how many questions
has she attempted incorrectly?
(ii) Mohini scores –5 marks in this test, though she has got 7 correct answers. How
many questions has she attempted incorrectly?
3. An elevator descends into a mine shaft at the rate of 6 m/min. If the descent starts
from 10 m above the ground level, how long will it take to reach – 350 m?
4. A submarine submerges at the rate of 5m/min. If it descends from 20m, above the sea
level, how long will it take to reach 250 m below the sea level?
5. A penalty in Meteor-Mania is -5 seconds. A penalty in Cosmic Calamity is -7 seconds.
Yolanda had penalties totaling -25 seconds in a game of Meteor-Mania and -35
seconds in a game of Cosmic Calamity. In which game did Yolanda receive more
penalties? Justify your answer.

Answer 1

Answer:

Profit earned by selling 1 pen = Re 1

Profit earned by 45 pens = Rs. 45, which we denote by + Rs. 45

Total loss given = Rs. 5, which we denote by Rs -5.

Profit earned + Loss incurred = Total Loss

Therefore, loss incured = Total Loss - Profit earned.

= Rs. (-5-45)

=Rs. (-50)= -5000 paise

Loss incurred by selling one pencil = 40 paise, which we write as -40 paise.

So, number of pencils sold = (−5000)÷(−40)=125 pencils.