Answer :Anita's age = 7 years
Basilio's age = 2.5 years
Step 1. Assign variables to Anita's and Basilio's ages.
Anita's age = A
Basilio's age = B
Step 2. Use the information given to form two equations.
Anita is 4-1/2 years older than Basilio
A = 4.5 + B
Three times Anita's age added to six times Basilio's age is 36
3A + 6B = 36
Step 3. Substitute the value of A from first equation in to the second equation and solve for B
3(4.5 + B) + 6B = 36
13.5 + 3B + 6B = 36
13.5 + 9B = 36
9B = 36 - 13.5
9B = 22.5
B = 22.5/9 = 2.5
Step 4. Find the value of A
A = 4.5 + 2.5 = 7
Answer:
Anita's age = 7 years
Basilio's age = 2.5 years
It means your solving for x
Answer:
C. 10 000
Step-by-step explanation:
If we called:
x = children who have been vacinated against rubella only
2x = children who have been vaccinated against mumps
y = children who have been vaccinated agains both
Children who have been vaccinated against mumps only = x - y
And we know that y = 2*(x-y)
=> 2y = 3x
y = 5000
There fore x = 7500
The number of children who have been vaccinated against rubella
= 2x - y = 2*7500 - 5000 = 15 000 - 5000 = 10 000
50 students participated in the survey, if you need help with 2, 3, & 4, just comment and ask
90/2 = 45
45/1700 = 0.02647
0.02647 x 100 = 2.64
2.46%