Answer:
1 hour
Step-by-step explanation:
Hello, let's say that her departure trip takes t in minutes, as her return speed is 3 times her departure speed, she took t/3 for the return and we know that this 40 minutes less, so we can write.
t/3=t-40
We can multiply by 3
t = 3t -40*3 = 3t - 120
This is equivalent to
3t -120 = t
We subtract t
2t-120 = 0
2t = 120
We divide by 2
t = 120/2 = 60
So this is 60 minutes = 1 hour.
Thank you.
Answer:
Step-by-step explanation:
The 5th term of the arithmetic sequence is 53. We can write the equation:
The 6th term of the arithmetic sequence is 62. We can write the equation:
Subtract the first equation from the second one to get:
The first term is
The 38th term of the sequence is given by:
Seven and Seventy-Five Hundredths
Answer: 2.28%
Step-by-step explanation:
μ = 71.8
σ = 3.4
X < 65
P(X < 65) = P (Z < 65 - 71.8/3.4) = P (Z < -2)
According to the table for the normal distribution attached, it will give us
P (z < Z < 0), this way, to find the P(Z < z), we need to do 0.5 - P:
0.5 - P(-2 < Z < 0) = 0.5 - 0.4772 = 0.0228
In percentage: 0.0228*100 = 2.28%
Answer:
x,y =2,1
Step-by-step explanation:
3x+4y=10 ................equ1
x-y=1 ................equ2
This system of equations forms a quadratic equation.
Lets use the substitution method in solving this set of equations
from equ 2; x=y+1
substitute x=y+1 into equ 1
3(y+1) +4y=10
3y+3+4y=10
7y=10-3
7y=7
y=7/7
y=1
but x=y+1
substitute the value of y into this equation to get x
x= 1+1
x=2
x,y=2,1
