Answers:
- Total equation: x+y = 80
- Legs equation: 2x+4y = 248
- How many ducks? 36
- How many cows? 44
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Further explanation:
- x = number of ducks
- y = number of cows
x+y = 80 is the total equation (ie the head count equation) since we assume each animal has 1 head, and there are 80 heads total.
That equation can be solved to y = 80-x after subtracting x from both sides.
The legs equation is 2x+4y = 248 because...
- 2x = number of legs from all the ducks only
- 4y = number of legs from all the cows only
- 2x+4y = total number of legs from both types of animals combined
We're told there are 248 legs overall, so that's how we ended up with 2x+4y = 248
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Let's plug y = 80-x into the second equation and solve for x.
2x+4y = 248
2x+4( y ) = 248
2x+4( 80-x ) = 248
2x+320-4x = 248
-2x+320 = 248
-2x = 248-320
-2x = -72
x = -72/(-2)
x = 36
There are 36 ducks
Now use this x value to find y
y = 80-x
y = 80-36
y = 44
There are 44 cows.
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Check:
36 ducks + 44 cows = 80 animals total
36*2 + 44*4 = 72 + 176 = 248 legs total
The answers are confirmed.
Answer:
=43.98
Step-by-step explanation:
put in calculator
43.98229715
Answer:
78 is the probability of spinning
Answer:
The sale is 5% off.
Step-by-step explanation:
- $25 regular price.
- $18.75 sale price.
You need to find the percentage that deducts $1.25 from the regular price. I start with 5% and work my way up from there until I find the answer.
So, <em>5</em><em>%</em><em> </em><em>of </em><em>2</em><em>5</em><em> </em><em>=</em><em> </em><em>?</em>
5% * 25 = 1.25
You needed $1.25, 5% gives you that.
Therefore, the answer is 5%.
Answer:
{-1, 3, 7, 11, 15}
Step-by-step explanation:
f(x) = 2x − 1, {0, 2, 4, 6, 8}
f(0) = 2*0 − 1 = 0 - 1 = -1
f(2) = 2*2 − 1 = 4 - 1 = 3
f(4) = 2*4 − 1 = 8 - 1 = 7
f(6) = 2*6 − 1= 12 - 1 = 11
f(8) = 2*8 − 1= 16 - 1 = 15