Answer:
<em>1) the exact distance = 9.428571429 feet</em>
<em>the approximate distance = 9.4 feet</em>
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<em>2) the exact area = 7.071428571 ft^2</em>
<em>the approximate area = 7 ft^2</em>
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Step-by-step explanation:
Required diameter d = 3 feet
1) The distance around the outside of the pit is the circumference of the circle that will be formed by this circular fire pit.
circumference of a circle is given as = πd = 
x 3 = 9.428571429 feet
the exact distance = 9.428571429 feet
the approximate distance = 9.4 feet
2) The area of the circle that will be formed = 
= 
= 7.071428571 ft^2
the exact area = 7.071428571 ft^2
the approximate area = 7 ft^2
Answer:
Step-by-step explanation:
Let's call hens h and ducks d. The first algebraic equation says that 6 hens (6h) plus (+) 1 duck (1d) cost (=) 40.
The second algebraic equations says that 4 hens (4h) plus (+) 3 ducks (3d) cost (=) 36.
The system is
6h + 1d = 40
4h + 3d = 36
The best way to go about this is to solve it by substitution since we have a 1d in the first equation. We will solve that equation for d since that makes the most sense algebraically. Doing that,
1d = 40 - 6h.
Now that we know what d equals, we can sub it into the second equation where we see a d. In order,
4h + 3d = 36 becomes
4h + 3(40 - 6h) = 36 and then simplify. By substituting into the second equation we eliminated one of the variables. You can only have 1 unknown in a single equation, and now we do!
4h + 120 - 18h = 36 and
-14h = -84 so
h = 6.
That means that each hen costs $6. Since the cost of a duck is found in the bold print equation above, we will sub in a 6 for h to solve for d:
1d = 40 - 6(6) and
d = 40 - 36 so
d = 4.
That means that each duck costs $4.
12.89 can be written as 1289/100, hence its a rational number.
