Quantitative aptitude question(CAT 2021)

Cat strategy

A watch loses 2/3% time during the 1st week and
gains 1/3% time during the next week. If on a Sun-
day noon, it showed the right time, what time will
it show at noon on the Sunday after the next.
(a) 11 : 26:24 a.m. (b) 10:52 : 18 a.m.
(c) 10:52:48 a.m. (d) 11:36 : 24 a.m.
Clocks A, B and C strikes every hour. B slows down
and takes 2 min longer than A per hour while C
become faster and takes 2 min less than A per hour.
If they strike together at 12 midnight, when will they
strike together again
(a) 10 a.m.
(b) 11 a.m.
(c) 9 p.m.
(d) 8 p.m.
A boat went down the river for a distance of 20 km.
It then turned back and returned to its starting point,
having travelled a total of 7 hours. On its return
trip, at a distance of 12 km from the starting point,
it encountered a log, which had passed the starting
point at the moment at which the boat had started
downstream. The downstream speed of the boat is
(a) 7 kmph
(b) 13 kmph
(c) 16 kmph
(d) 10 kmph
Two boats go downstream from point X to point Y.
The faster boat covers the distance from X to Y 1.5
times as fast as the slower boat. It is known that for
every hour the slower boat lags behind the faster boat
by 8 km. However, if they go upstream, then the fast-
er boat covers the distance from Y to X in half the time as the slower boat. Find the speed of the faster boat in still water.
(a) 12 kmph
(b) 20 kmph
(c) 24 kmph
(d) 25 kmph