Answer:
11. x = 5
12. x = 24
Step-by-step explanation:
11.
8x° + 140° = 180°
(Linear pair angles)
8x° = 180° - 140°
8x° = 40°
x ° = 40°/8
x° = 5°
x = 5
12.
2x° + 42° = 90°
(complementary angles)
2x° = 90° - 42°
2x° = 48°
x ° = 48°/2
x° = 24°
x = 24
12/5 = 2.4 beats per second
2.4 * 30 = 72 beats
Answer: x = 11
Step-by-step explanation:
First, add 3 to both sides
0.4x - 3 = 1.4
+3 +3
0.4x = 4.4
Then, divide each side by 0.4 to isolate x
x = 11
Answer:
2424.5
904.16
Step-by-step explanation:
the mean = ∑frequency /n
∑f = 5+17+36+115+125+81+47+45+22+7 = 500
∑xf = 1212250
∑x²f = 3347037625
sample mean = 1212250/500
= 2424.5
variance = 1/500-1[3347037625 - 1212250²]
= 815710.02
standard deviation is = √variance
standard deviation = √815710.02
= 904.16