Answer:
The amount of steel used = 94.38 
Step-by-step explanation:
Height of the tank = 4.5 m.
Diameter of the tank = 4.2 m.
But,
radius = 
= 
radius = 2.1 m
Total surface area of a cylinder = 2
rh + 2

= 2
r(r + h)
= 2 x
x 2.1 (2.1 + 4.5)
= 44 x 0.3 (6.6)
= 87.12
Total surface area of a cylinder = 87.12 
Since
of the steel was wasted, then;
x 87.12 = 7.26 
Actual area of steel sheet used = 87.12 + 7.26
= 94.38 
Thus, 94.38
of steel was used in making the tank.
Answer: The area common to both triangle is 31.77 sq. cm.
Step-by-step explanation:
Since we have given that
30-60-90 triangles are placed.
So, the ratio of sides would be

Since Hypotenuse = 12 cm
So, it becomes,

So, Base would be

and Perpendicular would be

So, Area common to the both triangles would be

Hence, the area common to both triangle is 31.77 sq. cm.
William is 17 years old and Charmaine is 14 years old.
Step-by-step explanation:
Let x be the age of William and y be the age of Charmaine
Then
William is 3 years, older than Charmine.
x = y+3 Eqn 1
The sum of 3 times Charmaine's age and 2 times William's age is 76.
2x+3y = 76 Eqn 2
Putting x = y+3 in Eqn 2

Hence,
William is 17 years old and Charmaine is 14 years old.
Keywords: Linear equations, Variables
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Answer:
A picture of the problem might help
It should be 7 tens because both side should be equal.