To solve this problem, let us first assign some
variables. Let us say that:
x = pigs
y = chickens
z = ducks
From the problem statement, we can formulate the
following equations:
1. y + z = 30 --->
only chicken and ducks have feathers
2. 4 x + 2 y + 2 z = 120 --->
pig has 4 feet, while chicken and duck has 2 each
3. 2 x + 2 y + 2 z = 90 --->
each animal has 2 eyes only
Rewriting equation 1 in terms of y:
y = 30 – z
Plugging this in equation 2:
4 x + 2 (30 – z) + 2 z = 120
4 x + 60 – 2z + 2z = 120
4 x = 120 – 60
4 x = 60
x = 15
From the given choices, only one choice has 15 pigs. Therefore
the answers are:
She has 15 pigs, 12 chickens, and 18 ducks.
The anwser would be -15
3 x (-5) = -15
So each 1 revolution it travels the distance around the rim of the wheele aka circumference
circumference=pi times diameter
diameter=21
circunference=pi times 21 or 21pi
so distance=number of revolutions times circunference
number of revolutions=3
subsitute
distance=3 times 21pi
distance=63pi
answer is 63pi
or aprox pi to 3.14 and do 63 times 3.14=197.82
aprox 197.82 inches
1/2 b-39=101
+39 +39
1/2 b= 140
2(1/2) b= 140(2)
b=280