Let AB be a chord of the given circle with centre and radius 13 cm.
Then, OA = 13 cm and ab = 10 cm
From O, draw OL⊥ AB
We know that the perpendicular from the centre of a circle to a chord bisects the chord.
∴ AL = ½AB = (½ × 10)cm = 5 cm
From the right △OLA, we have
OA² = OL² + AL²
==> OL² = OA² – AL²
==> [(13)² – (5)²] cm² = 144cm²
==> OL = √144cm = 12 cm
Hence, the distance of the chord from the centre is 12 cm.
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Answer:
Your favorite radio station in a given year plays 105120 songs.
Step-by-step explanation:
Lets make some assumptions:
1. A radio program in average last 50 minutes, because 10 of them are for commercials.
2. a song average length is about 3 minutes
3. the speakers use 10 to 20 minutes of the radio program.
4. So, in an hour just 30 minutes are effectively used to play songs on a radio station. That results in 10 per hour at least, and 13.3 at most. So lets settle an average of 12 songs per hour.
5. The radio station plays songs 24 hours a day unstoppable.
Now:
A day has 24 hours, a week seven days and therefor (24*7= 168 hours) 168 hours in a week.
A year has 52.1429 weeks, so it has 8760 Hours (52.17429weeks*168hours=8760 hours )
So:
8760 hours in a year
12 songs per hour
