136. A person walking at 5/6th of his usual speed is 40 minutes late to his office. What is his usual travel time to his office?

A. 3 hours 20 minutes
B. 3 hours 15 minutes
C. 3 hours 30 minutes
D. 3 hours
✅ The correct answer is option A. 3 hours 20 minutes.
Let his usual speed be x kmph, the distance to his office be y km and his usual travel time be t hrs. y = xt = (5/6)x * (t+(40/60)) Solving the equation,

t = 3.33 hrs = 3 hrs 20 minutes

125. A is thrice as good a work man as B and takes 10 days less to do a piece of work than B takes. B can do the work in:___________?

A. 15 days
B. 14 days
C. 16 days
D. 30 days
✅ The correct answer is option A. 15 days.
Raio of times taken by A and B = 1 : 3

If the difference of time is 2 days, B takes 3 days. If the difference of time is 10 days.

B takes [3/2×10]=15 days

123. A man sells Rs.5000, 12 % stock at 156 and uinvests the proceeds parity in 8 % stock at 90 and 9 % stock at 108. He hereby increases his income by Rs. 70. How much of the proceeds were invested in each stock?

A. 3600(8%), 4200(9%)
B. 4000(8%), 4200(9%)
C. 3600(8%), 4000(9%)
D. 4000(8%), 4000(9%)
✅ The correct answer is option A. 3600(8%), 4200(9%).
S.P of Rs. 5000 stock = Rs. [(156/100)*5000] = Rs. 7800.

Income from this stock = Rs. [(12/100)*5000] = Rs. 600.