Answer:
Here's a rainbow of logic.
Step-by-step explanation:
Answer:
where is the expression
Step-by-step explanation:
(^_^)(^_^)(^_^)
Answer: 52.94
Step-by-step explanation:
Length of train A = 480m
Tunnel length = 1320m
Time taken to cross tunnel = 2 mins = 120sec
Length of train B = 420m
Train B is slower than train A
Difference between their speed = 18km/hr
18km/hr = (18×1000)/3600 = 5m/s
Speed of train A :
Speed = distance / time
Speed = 1320 / 120 = 11m/s
Therefore, speed of train B :
(11 - 5)m/s = 6m/s
Relative speed of the two trains is therefore;
(Speed of A + speed of B)
Note : they are moving in opposite direction
( 11 + 6)m/s = 17m/s
Therefore time taken to cross each other :
(Sum of the length of both trains / relative speed of the trains)
Time taken = (480m + 420m) / (17m/s)
Time taken = 900m / 17m/s
Time taken = 52.94s
Answer: 5x2^5
Step-by-step explanation: Divide 160 by 2 as many times as you can to get 80x2, 40x2x2, 20x2x2x2, 10x2x2x2x2, 5x2x2x2x2x2. Then re-write your answer so that it is 5x2^5.
Answer:
1191.4 ; 34.5
Step-by-step explanation:
Given the data:
29; 37; 38; 40; 58; 67; 68; 69; 76; 86; 87; 95; 96; 96; 99; 106; 112; 127; 145; 150
The sample variance and standard deviation can be obtained thus :
Σ(X - m)² / (n - 1)
Where, m = mean of the sample
n = sample size
The standard deviation equals, sqrt(variance )
Using a calculator:
The variance, σ² ;
Mean = Σx / n = 1681 / 20 = 84.05
(x -m)^2
[(29-84.05)^2 + (37-84.05)^2 + (38-84.05)^2 + (40-84.05)^2 + (58-84.05)^2 + (67-84.05)^2 + (68-84.05)^2 + (69-84.05)^2 + (76-84.05)^2 + (86-84.05)^2 + (87-84.05)^2 + (95-84.05)^2 + (96-84.05)^2 + (96-84.05)^2 + (99-84.05)^2 + (106-84.05)^2 + (112-84.05)^2 + (127-84.05)^2 + (145-84.05)^2 + (150-84.05)^2] / 19
22636.95 / 19
= 1191.4184 = 1191.42
Standard deviation = sqrt( Variance)
Standard deviation = sqrt(1191.4184)
Standard deviation = 34.516929 = 34.52