Answer:
402.123859659
Step-by-step explanation:
first we use A=πr2
this gives us A = 16π
Then multiply by 8 to get 128π
128π = 402.123859659
Answer:
-2
Step-by-step explanation:
x+3+4=5
x+7=5
subtract 7 on both sides
x=-2
Answer:
C) $20.80
Step-by-step explanation:
1 kg of cooking oil = $6.5
1 packet of cooking oil =2/5 kg
If 1 kg of cooking oil = $6.5
2/5kg of cooking oil = $X
Cross Multiply
1kg × $X = 2/5kg × $6.5
$X = 13/5
$X = 2.6
Hence 2/5kg of oil cost $2.6
Since 1 packet of oil = 2/5kg of oil , 1 packet of oil cost $2.6
The amount she spent if she bought if she bought 8 packets of the cooking oil is calculated as:
1 packet of oil = $2.6
8 packets of oil =
$2.5 × 8
= $20.80
Therefore,if Sara bought 8 packets of oil, the amount she would spend = $20.80
The best way to solve a problem like this is to set up two equations. First assign a variable to each thing you are trying to find. In this case, it's two different kinds of cars. Let's call the cars that weigh 3,000 pounds x, and the ones that weigh 5,000 y. The two equations you should write are:
x+y=18 (because the problem tells you there were 18 cars in total)
3000x+5000y=60000 (because that is the total weight in the problem)
Next, you need to solve for one of the variables. I will solve for x first by subtracting y from both sides of the first equation.
x=18-y
Then you have to plug that into the other equation to get:
3000(18-y)+5000y=60000
Simplify and solve for y:
54000-3000y+5000y=60000
54000+2000y=60000
2000y=6000
y=3
Now that you know what y equals, you can put it into the equation we solved for x:
x=18-3
x=15
So there are 15 cars that weigh 3000 pounds and 3 that weigh 5000.
