Answer:
The correct answer is A.
Step-by-step explanation:
The area of a rectangle can be calculated using the following formula:

If we know that the area measures
and one side of the figure measures 4.2 m, we can say that:

We isolate the side we don't know:

So I = 9 m
To know the perimter of a rectangle, we use the following formula:



Answer:
The farmer bought 36 pigs in all.
Step-by-step explanation:
Given that a farmer bought a number of pigs for $ 160, but, however, 8 of them died before he could sell the rest at a profit of 6 per pig, and his total profit was $ 8, to determine how many pigs did he originally buy the following calculation must be performed:
160 + 8 = 168
168/6 = 28
28 + 8 = 36
Thus, the farmer bought 36 pigs in all.
<span>So we want to know how much ball bearings can be made with 5.24 cm^3 if one ball bearing has a diameter of 1 cm. We know that radius r=d/2=0.5cm So the volume V of one ball bearing is: V=(4/3)*pi*r^3 so V=(4/3)*3.14*(0.5)^3cm^3=0.524cm^3. Now we simply divide the volume of steel by the volume of the ball bearing: 5.24/0.524=10. So we can make 10 ball bearings from 5.24 cm^3 of steel</span>
Answer:
14 pounds
Step-by-step explanation:
The given equations can be solved for y by substituting for x. The first equation is convenient for writing x in terms of y.
<h3>Solution</h3>
x = 20 -y . . . . . . . subtract y from the first equation
7(20 -y) +5.5y = 119 . . . . . substitute for x in the second equation
140 -1.5y = 119 . . . . . . . . simplify
21 = 1.5y . . . . . . . . . . . add 1.5y -119 to both sides
14 = y . . . . . . . . . . . .divide by 1.5
14 pounds of soy nuts should be used in the mixture.
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<em>Additional comment</em>
There are many ways to solve a system of two linear equations. The attachments shows a matrix solution using a suitable calculator. It tells us that x=6 and y=14, as we found above.
Answer:
10000 (1sf)
12000(2sf)
11900(3sf)
11940(4sf)
Step-by-step explanation:
I would go for 12000 (2sf) if it the degree of accuracy isn't specified in the question