# Clock Puzzles 7 [With Answers]

Explanation: From Left to Right, The time on the watches increases by 2 hours 3 minutes, then decreases by 1 hour 16 minutes, alternately.

Explanation: On each watch, the time shown contains two digits that are the same.

Explanation: From left to right, add 1 to the value of each digit on the watch, and rotate the digits one place to the left.

Puzzle 4: Calculate the angle between the two hands of clock when the clock shows 4 : 20 p.m. ?

A) 5 degrees              B) 10 degrees

C) 15 degrees            D) 25 degrees

Answer: B) 10 degrees

Explanation: Since at 4 : 20 the minute hand will be at 4 and the angle between them will be same as the distance covered in degree by the hour hand in 20 minutes.

Required angle = distance of hour hand = speed × time = ½ × 20 =10 degrees.

Puzzle 5: If a Siren sounds for every 5 seconds, how many times will it sound in ¾ of an hour?

A) 541 times                   B) 540 times

C) 450 times                  D) 275 times

Answer: A) 541 times

Explanation: There are 60 minutes in an hour.

In ¾ of an hour there are (60 × ¾) minutes = 45 minutes.

In ¾ of an hour there are (60 × 45) seconds = 2700 seconds.

Siren sounds for every 5 seconds.

In 2700 seconds 2700/5 = 540 times.

The count start after the first sound, the Siren will sound 541 times in ¾ of an hour.