In this blog, we will discuss 6 questions that are likely to be asked in GATE 2021. The topics which are covered in this blog are Problems on ages, compound interest, simple interest and algebra.
In 2002, Badhul’s age was one third age of Rishabh. In 2010 Badhul’s age was half the age of Rishabh. What is Badhul’s year of birth?
solution
In 2002, Badhul’s age is one third age of Rishabh so, B = R/3 or R = 3B
In 2010, B+8 = (R+8)/2
2(B+8) = 3B + 8
2B + 16 = 3B + 8
B = 8
R = 3B = 24
The year of birth of Badhul is 1994
Govind Purchases 3 Bulbs, 7 Sockets, and 1 Fan and pays Rs. 1200 on the first day. The next day, he purchases 4 Bulbs, 10 sockets, and 1 Fan from the same shop and pays Rs. 1645. Then how much he had to pay if he purchases 1 Bulb, 1 Socket and 1 Fan on the third day from the same shop and prices remained unchanged?
Solution
[3B+ 7S + 1F = 1200]….(1)
[4B + 10S + 1F = 1645] ….(2)
subtract equation 1 and 2 then you will get,
-B – 3S = -445
B + 3S = 445
4B + 10S + 1F = 3B + 9S + (1B + 1S +1F) = 1645
1645 = 3[B + 35] + ( 1B + 1S + 1F)
1645 = 3 x 445 + (1B + 1S + 1F)
1B + 1S + 1F = 310 Ans