Answer:
140°
Step-by-step explanation:
1. full the circle is 360°;
2. YZ+XY=360-80; ⇔ YZ+XY=280;
3. if YZ=XY, then YZ=XY=280/2=140, ⇒ YOZ=140°
There are 20 cassettes.
Step-by-step explanation:
Given,
Ratio of cassette to compact disc = 10:3
Let,
the number of cassettes = 10x
Number of compact disc = 3x
According to given statement;
the number of cassettes is 10 less than 5 times the number of compact discs.
10x = 5(Number of CD) - 10

Dividing both sides by 5

Number of cassettes= 10x = 10(2) = 20
There are 20 cassettes.
Keywords: variable, ratio
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50.1 repeateding because that is the only positive number