Answer:
3
Step-by-step explanation:
mhm for your brother
anyways...
2x-3+6x = 21
Adding like terms
8x -3 = 21
Adding 3 on both sides
8x = 24
Dividing both sides by 8
x = 3
Alright
so
28% of 2 m³=0.28 times 2=0.56 m³ of silt in the first mixture
13% of the 1 m³=0.13 times 1=0.13 m³ of silt in 2nd
total is 0.56 m³+0.13 m³=0.69 m³ of silt
and the total is 2m³+1m³=3m³
so
0.69/3=0.23=23%
answer is D
Answer:
1.60 
Step-by-step explanation:
Assuming that this is a cylindrical pipe, the area can be determined by applying the formula for calculating the area of a circle.
i.e Area = 

So that,
for the inner part of the pipe,
r = 
= 
= 2.5 feet
Area of the inner part of the pipe = 

= 3.14 x 
= 19.625
Are of the inner part of the pipe is 19.63
.
Total diameter of the pipe = 5 + 0.2
= 5.2 feet
r = 
= 2.6 feet
Area of the pipe = 

= 3.14 x 
= 21.2264
Area of the pipe is 21.23
.
Thus the cross sectional area = Area of the pipe - Area of the inner part of the pipe
= 21.2264 - 19.625
= 1.6014
The cross sectional area of the cement pipe is 1.60
.
The tree diagram for the probability is shown below
P(Clay|Positive) is read 'Probability of Clay given the result is Positive'.
This is a case of conditional probability.
The formula for conditional probability is given as
P(Clay|Positive) = P(Clay∩Positive) ÷ P(Positive)
P(Clay∩Positive) = 0.21×0.48 = 0.1008
P(Positive) = P(Rock∩Positive) + P(Clay∩Positive) + P(Sand∩Positive)
P(Positive) = (0.53×0.53) + (0.21×0.48) + (0.26×0.75)
P(Positive) = 0.2809 + 0.1008 + 0.195
P(Positive) = 0.5767
Hence,
P(Clay|Positive) = 0.1008÷0.5767 = 0.175 (rounded to 3 decimal place)