-2 and+2 =0
1/2 -3/2= -2/2 or -1
7-1=6
Answer: 3 kids take 3 pieces of candy each
Step-by-step explanation:
Let the number of children that took 3 pieces is x ( total take 3*x pieces of candy)
Number of children that took 5 pieces is y ( total take 5*y pieces of candy)
1 child took 1 piece that actually means that x+y=18 and 3*x+5*y=84.
( Because total number of all kids is 19. We just deduct one kid (Let his name is John) who took only 1 candy. So we have 19-1 =18 kids without John. The similar is with the candies. Total number is 85. We deduct 1 piece which John has taken. )
So we have 2 equations or the system of 2 equations:
1). x+y=18
2). 3*x +5*y=84
Multuply both sides of equation 1) by 3
We have 3*x+3*y=18*3
Deduct 3*y from both sides of this equation
3*x+3*y-3*y=54-3*y
3*x=54-3*y
Substitute 3*x in equation 2). by 54-3*y
2) 54-3*y+5*y=84
2*y=30
y=15 ( kids take 5 pieces of candy each)
Using equation 1) find x
x+15=18
x=3 (kids take 3 pieces of candy each)
Area of the circle can be calculated using the following rule:
area = pi*(radius)^2
For the first circle:
We are given that:
area = 1040.9 square units ....> I
For the second circle:
We are given that:
radius = 27 units
Therefore:
area = pi * (27)^2 = 2290.221044 square units ....> II
For the third circle:
We are given that:
circumference = 87.92 units
Therefore:
circumference = 2*pi*radius = 87.92
radius = 13.99 units
area = pi*(13.99)^2 = 615.12799 square units ...> III
For the fourth circle:
We are given that:
diameter = 19 units
Therefore:
radius = 19/2 = 9.5 units
area = pi*(9.5)^2 = 283.528 square units ....> IV
Based on the above, the order according to increasing area would be:
IV , III , I , II
hope this helps :)
Answer:
Ok:
Step-by-step explanation:
I see that you set up 90 miles = 60 mph * t, where you found out that t = 1.5. What what you needed to do was set 180 miles = 45 mph * t. This is because it is 45 mph for the <em>whole</em> trip. Then, you find that t = 4 hours. That that means that he spent 2.5 hours driving back. Then, we can do d=vt and find 90/2.5 as the speed he went home at. Which comes out to be 36 mph.
