Set up the equation of two ratios:
3 racks 36 racks
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15 min x
Solve this for x: 3x =540; x = 180 minutes, or 3 hours
-2m - 5m - 8 = 3 + (-7) + m
-7m - 8 = 3 - 7 + m
-7m - 8 = m - 4 <=== here is one
m - 4 = -7m - 8 <=== another one
-8 - 7m = -4 + m <== and another one
The answer is C: systematic sampling
Answer:
x = 90°
y = 40°
z = 40°
Explanation (Concepts) :
A straight line has total 180° angle. A square has 4 sides of each 90° angle. A triangle is build up of 180° interior angle.
Workouts:
z + 90° + 50° = 180°
z = 180° - 90° - 50°
z = 40°
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x + 90° = 180°
x = 180° - 90°
x = 90°
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50° + 90° + y = 180°
y = 180° - 90° - 50°
y = 40°
