$30.25
$34.60
$38.90
What is the best estimation for the amount that Jason spent on gas last month?
A) 20 + 30 + 30 + 40
B) 20 + 30 + 35 + 40
C) 25 + 30 + 35 + 40
D) 30 + 30 + 35 + 40
solve with every step
7(1 - 2x) = -x + 33
Distribute 7 inside the parentheses.
7 - 14x = -x + 33
Subtract 7 from both sides.
-14x = -x + 26
Add x to both sides.
-13x = 26
Divide both sides by -13.
x = -2
x= -2
my friend included the steps above
first laptop: $700
second laptop: $400
third laptop: $200
B.
first laptop: $700
second laptop: $200
third laptop: $400
C.
first laptop: $650
second laptop: $250
third laptop: $400
D.
first laptop: $650
second laptop: $200
third laptop: $450
E.
There is not enough information to solve for the unknowns.
Option: A is the correct answer.
A.
first laptop: $700
second laptop: $400
third laptop: $200
Let the cost of first laptop be: x
Second laptop be: y
and cost of third laptop be: z
Now, it is given that:
Adam bought three laptops for his office at a total cost of $1,300.
This means that:
x+y+z=1300---------(1)
on doubling the price of the first laptop and tripling the price of the third laptop, the total cost increased to $2,400.
This means that:
2x+y+3z=2400-------(2)
He spent $100 more on first laptop than the combined price of the second and third laptops.
This means that:
x-(y+z)=100------------(3)
On using equation (1) we have:
y+z=1300-x
Keeping the value of y+z in equation (3) we get:
x-(1300-x)=100
x-1300+x=100
2x=100+1300
x=1400/2=700
Hence, price of first laptop is: $ 700.
Now on putting the value of x in equation (1) and (2) we get:
y+z=600 ⇒ y=600-z------(4)
and y+3z=1000 (from equation (2) )
⇒ 600-z+3z=1000
⇒ 600+2z=1000
⇒ 2z=1000-600
⇒ 2z=400
⇒ z=200
Hence, cost of third laptop is: $ 200
and cost of second laptop is: $ 400
( since on putting the value of z in equation (4) )
A.
first laptop: $700
second laptop: $400
third laptop: $200
b Which state has the smallest population?
C. About what percentage of Americans do not live in California, New York, or Texas?
Convert all statistics into percentages:
CA: 3/25=0.12 -> 12%
NY: 3/50=0.06 -> 6%
TX: 2/25=0.08->8%
(A) Out of the three states, California has the largest population
(B) Out of the three states, NY has the smallest population
(C) USA=100%, CA+NY+TX=26%, therefore 74% of USA do not live on those three states.