General Maths Puzzle Numerical Ability

There are two sand-glass timers.One of them takes 7 minutes for
sand to filter through and the other takes 11 minutes.How will you
use the two sand glass timers to measure 15 minutes of time?

Read Solution (Total 2)

1st of all start both timer at same time
when 1st (7 min) timer over than 1st and 2nd timer both will change (cover 7 min)
and than 2nd (11 min) timer has to change (cover 4 min)
after completing 2nd, 1st time has to change,(cover 4 min) (total=7+4+4=15 min)
10 years agoHelpfull: Yes(2) No(0)

Let both the sand glass filter at the same time.....after 7mins reverse the 7mins glass until 11mins glass in filtered..n after 11mins glass is filtered completely keep it aside and reverse the 7mins glass..15mins are measured.
10 years agoHelpfull: Yes(0) No(0)

General Other Question

Three friends went to a hotel and they want to stay in a room and they asked the manager the cost of room to stay for one night he said 30 rupees. then each gave 10 rupees and finally they gave 30Rs. Then they went to room ,suddenly manager remembered that room costs 25Rs. He gave 5Rs to boy to give to friends. The boy took 2Rs in that and he distributed 3Rs among the three. so each paid 9RS total 3*9=27 and the boy has 2Rs with him so 27+2=29
finally where is the 1Rs Planet A has 36 hours in a day,90 minutes in an hour and 60 seconds in a minute. It has same pattern as our watch. Find angle between hour hand and minute hand at 9:40 in the morning?