Answer:
45 old houses
Step-by-step explanation:
new houses : old houses
3 : 9
15 : ?
(3 = 1st ratio and 9 = 2nd ratio)
To find the missing ratio, divide the first ratio from the new ratio:
15 / 3 = 5
Take the product and multiply that by the second ratio to find the missing ratio:
9 x 5 = 45
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.
Slope is 2 and the y intercept is 4
The answer is C <<<=====
It can't be anything else. It is not a right angle. A>90
It can't be acute because one angle is greater than 90.
It can't scalene because at least 2 of the angles (and 2 sides) are equal.
Answer: Terry should buy the half-liter of water that costs $2.11 because buying 200 litres here is cheaper.
Step-by-step explanation:
Terry is buying water and needs 22 liters. A half-liter of water costs $2.11. Using this information, 22 litres will cost:
= 22 ÷ 1/2 × 2.11
= 22 × 2 × 2.11
= $92.84
Also, A 200 -milliliter container of water costs $1.01. Using this information, 22 litres will cost:
= 22 × 1.01 ÷ 200/1000
= 22 × 1.01 × 1000/200
= 22 × 1.01 × 5
= $111.1
Based on this information, Terry should buy the half-liter of water that costs $2.11 because buying 200 litres here is cheaper.
