Quantitative Aptitude

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1.
If x*y = 3x + 2y, Then 2*3 + 3*4 is equal to :
2.
If a * b = a + b + ab, then 3 * 4 - 2 * 3 is equal to
3.
If a * b = 2a - 3b + ab, then 3 * 5 + 5 * 3 is equal to :
4.
If a * b = 2 (a + b), then 5 * 2 is equal to :
5.
There are 100 students in 3 sections A, B and C of a class. The average marks of all the three sections was 84. The average of B and C was 87.5 and the average marks of students in A section was :