Answer: The answer is 4 and 32.
Step-by-step explanation: Let "A", "B" and "C" represents the set of students who were taking Arabic, Bulgarian and Chinese respectively.
The, according to the given information, we have

Let 'p' represents the number of students who take all the three languages, then

Also,

From here, we get after subtracting equation(c) from (b) that
Therefore,
and from equation (a), we find

Thus,
and

Thus, the number of students who take all the three languages is 4 and the number of students who take none of the languages is 100-68 = 32.
Answer:

Step-by-step explanation:
Given: In a parallelogram ABCD, diagonals intersect at O and ar(ABCD) is
.
We need to find the area of triangle AOB.
We know that each diagonal divide the parallelogram in two equal parts and diagonals bisect each other.
It means both diagonals divide the parallelogram in 4 equal parts.



Hence, the values of ar(AOB) is
.
The number 4.2 from the set will make the equation x+2=6.2 true.