Answer:
7 are boys
Step-by-step explanation:
Make a system of equations where g is for girls and b is for boys.
b+g=26
g=3b-2
Substitute "3b-2" in for "g" in the first equation.
b+(3b-2)=26
Rewrite without the parentheses because it's addition and not multiplication.
b+3b-2=26
Combine like terms.
4b-2=26
Add 2 to both sides.
4b=28
Divide by the coefficient of the variable to get it alone.
b=7
Answer:
Adult ticket: $7
Child ticket: $2
Step-by-step explanation:
Set up a system of equations where a represents the cost of one adult ticket and c is the cost of one child ticket:
2a + 3c = 20
a + 4c = 15
Solve by elimination by multiplying the bottom equation by -2:
2a + 3c = 20
-2a -8c = -30
Add them together:
-5c = -10
c = 2
Now, we can plug in 2 as c to find the value of a:
2a + 3c = 20
2a + 3(2) = 20
2a + 6 = 20
2a = 14
a = 7
Complementary angles add up to 90*. Therefore, the logical answer would be
D, 77.
Answer: Choice C and Choice D
========================================================
Explanation:
- Choice A doesn't work because it the $1 should be $7 instead.
- Choice B doesn't work because it should be Elena spending $7 total on 3 notebooks and a $1 pen. The x is the amount per notebook.
- Choice C does work. If x is the number of grapes Noah gives each friend, then 3x is the total amount Noah gives over. Then 3x+1 is the number of grapes total. That +1 at the end is the grape Noah eats. We end up with 3x+1 = 7 because Noah starts off with 7 grapes.
- Choice D works also. The x is the number of hours for math, science and history each. So 3x is the combined time of those three classes. Add on 1 to get 3x+1 to represent all 7 hours, ie 3x+1 = 7.
- Choice E does not work. If it was her spending $7 on 3 markers and a $1 pen, then it would work.
Answer:
Step-by-step explanation:
We want to study the fuel consumption of each car, i.e the amount of mile per gallon the cars will consume
Step one:
given data:
First car
distance covered= 41 1/2 = 41.5miles
amount of gallons= 1 1/4= 1.25gal
the miles per gallons= 41.5/1.25=33.2 miles per gallon
Second car
distance covered= 21 3/5= 21.6miles
amount of gallons=4/5= 0.8gal
the miles per gallons= 21.6/0.8=27 miles per gallon
1. Therefore the unit rate of
the first car = 33.2 miles per gallon
the second car=27 miles per gallon
2. the first car can travel a greater distance on 1 gallon of gasoline
