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
2 years is the same as 24 months, so the equation would be:
685 = 24x + 85, where x is the monthly fee.
600 = 24x
600/24 = x
x = 25
The monthly fee is $25.
The <em><u>correct answer</u></em> is:
At least 7 times.
Explanation:
Since 10% of the water in the jug is removed each time, this means that 100-10=90% of the water remains.
After two times, we would have 0.9(0.9) = 0.81 = 81% of the water; each time she pours, the number of times 0.9 is multiplied by itself changes. This makes this an exponential inequality (it is not an equation, as we want "less than half of the water"):

To solve this, we will use logarithms:

59
47 - 11 = 36
23 + 36 = 59
I hope this helps. Brainliest appreciated.