All MCQs

Total expenses are Rs. 100,000.
Salaries are Rs. 50,000, which is 50% of the total.

The total production is 210 units.
Dividing by 4 gives 52.5 units.

Use inclusion-exclusion: 80 + 60 - 20.
This gives 120 people who prefer at least one.

A full pie chart is 360°.
Thus, 72/360 × 100 = 20%.

If 55% are girls, then 45% are boys.
Forty-five percent of 480 is 216.

The increase is 210 - 120 = 90 units.
The percentage increase is 90/120 × 100 = 75%.

A square matrix is invertible only when its determinant is nonzero.
A zero determinant means the matrix is singular.

An identity matrix has 1s on the main diagonal and 0s elsewhere.
It leaves a compatible matrix unchanged under multiplication.

For [[a, b], [c, d]], determinant = ad - bc.
Thus, 2 × 4 - 3 × 1 = 5.

Matrix addition is performed entry by entry.
Each corresponding pair sums to 5.

Matrix order is written as rows by columns.
Therefore, 3 rows and 4 columns give order 3 × 4.

Range equals maximum minus minimum.
Thus, 40 - 12 = 28.