Answer:the number of hot dogs is 10
Step-by-step explanation:
Let x represent the number of hamburgers.
Let y represent the number of hot dogs.
The ratio of hamburgers to hot dogs is 6 to 5. This means that the ratio of x to y is 6/5
x/y = 6/5
5x = 6y
x = 6y/5
Three times the number of hot dogs is 6 more than twice the number of hamburgers. This means that
3y = 2x + 6 - - - - - - - - -1
Substituting x = 6y/5 into equation 1, it becomes
3y = 2(6y/5) + 6
3y = 12y/5 + 6
Multiplying both sides of the equation by 5, it becomes
15y = 12y + 30
15y - 12y = 30
3y = 30
y = 30/3 = 10
x = 6y/5 = 6×10/5
x = 60/5 = 12
The constant is his speed (20 mph)
and equation would be d = 20t,
where
d - distance
t - time
Multiply 4.50 by 0.07
4.50*0.07 = 0.315
Then the sales tax is about $0.32.
You can also do it mentally. Moving the decimal point in 4.50 once to the left gives you 10% of the original amount, 0.45. Move it again to get 1% of the price, 0.045. Then multiply this by 7 to get 7%.
Answer:
Judy is 16 years old
Step-by-step explanation:
J = Judy's age
A = Adams age
J = 2A
Six years ago (subtract 6 from the ages)
(J-6) = 5*(A-6)
Distribute
J-6 = 5A - 30
Substitute J = 2A
2A -6 = 5A -30
Subtract 2A from both sides
2A-2A -6 = 5A-2A -30
-6 = 3A -30
Add 30 to each side
-6+30 = 3A-30+30
24 = 3A
Divide by 3
24/3 = 3A/3
8 = A
Adam is 8 years old now
We need to find Judy's age
J = 2A
J = 2*8
J = 16
Judy is 16 years old
