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30 POINTS!! EASY MATH PROBLEM!!!!!!!! PLEASE ANSWER CORRECTLY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

PROBLEM:
If the minute hand of a clock is 20° behind the hour hand at this moment, then in 18 minutes, the minute hand will be how many degrees ahead of the hour hand?

User EversMcc
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7.6k points

2 Answers

2 votes
Each minute on a clock face corresponds to an angle of

360/60 = 6 deg.

So in 18 minutes, the minute hand advances by 18 * 6 = 108 deg.

The hour hand advances at 1/12 of the rate of the minute hand, so in 18 minutes it advances by
108/12 = 9 deg.

In 18 minutes, the minute hand is ahead of the hour hand by

(108 - 9 - 20)
= 79 deg.
User ZenTheo
by
7.2k points
6 votes
1/18
5/60
1/12
60/12
5
|
6^•per min
18*6=108^• in 18 min hand
30^• per hour
1/2per min
9^•
108^•-20=88^•
88^•-9^•=79^•
Answer= 79 degrees
(Don't try to understand my work, I'll get a headache. If u need an explanation, let me know)
User Cypherjac
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7.4k points