Answer:
The value of x would be
or 
Step-by-step explanation:
Given,
x tons of 10% gravel G mixture is mixed with y ton of 2% gravel G to obtain 5% gravel mixture,
Thus, gravel G in x ton + gravel in y ton = gravel G in the resultant mixture,
⇒ 0.1x + 0.02y = 0.05(x+y),
0.1x - 0.05x = 0.05y - 0.02y
0.05x = 0.03y

Now, resultant mixture is z ton,
i.e. 

From equation (1),




Length of train : 100
length of bridge : 400
distance covered by the train to cross the bridge : (100 + 400) = 500
time taken by the train to cross : 30
speed = distance / time
speed = 500/30
speed = 16.67 meters per second <===
Answer: Length of the radius of the sector is 6 units.
Step-by-step explanation:
Since we have given that
Length of an arc = 10.8
Radian of a central angle = 1.8
First we convert radian into degrees,

As we know the formula for "Length of an arc":

Hence, Length of the radius of the sector is 6 units.
A Z-score helps us to understand how far is the data from the mean. The correct option is B.
<h3>What is Z-score?</h3>
A Z-score helps us to understand how far is the data from the mean. It is a measure of how many times the data is above or below the mean. It is given by the formula,

Where Z is the Z-score,
X is the data point,
μ is the mean and σ is the standard variable.
The weight of a randomly selected pack of gum has a z-score of 3.11. Therefore, The weight of this pack of gum is heavier than the mean weight by 3.11 standard deviations.
Hence, the correct option is B.
Learn more about Z-score:
brainly.com/question/13299273
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