Mathematics - MCQ Practice Questions
Practice free Mathematics multiple-choice questions with detailed answers and explanations. Perfect for competitive exam preparation.
30 questions | 100% Free
If x, y, z are in arithmetic progression and x + y + z = 15, then the middle term is:
Step 1: Set up the arithmetic progression.
When three numbers are in arithmetic progression, they can be written as
where a is the middle term and d is the common difference.
Step 2: Apply the sum condition.
Step 3: State the result.
Therefore, the middle term is
If p and q are roots of x² - 5x + 6 = 0, then the value of (1/p + 1/q) is:
Step 1: Apply Vieta's Formulas
For the quadratic x2−5x+6=0, Vieta's formulas give:
Step 2: Simplify the Expression
Combine the fractions algebraically:
Step 3: Substitute and Evaluate
This approach avoids finding the individual roots and uses the relationship between them directly.
Final Answer:
In a right-angled triangle, the altitude drawn to the hypotenuse divides it into segments of lengths 9 cm and 16 cm. What is the length of the altitude?
Step 1: State the Geometric Mean Altitude Theorem
When an altitude is drawn from the right angle to the hypotenuse of a right triangle, the altitude is the geometric mean of the two segments into which it divides the hypotenuse. That is, if the two segments have lengths p and q, then
Step 2: Identify the Known Values
The altitude divides the hypotenuse into two segments of lengths
Step 3: Apply the Theorem
Substituting into the formula:
Result
This is a fundamental property of right triangles, frequently applied in competitive examinations. The length of the altitude drawn to the hypotenuse is
In triangle ABC, point D lies on BC such that AD is the angle bisector. If AB = 6 cm, AC = 9 cm, and BD = 4 cm, what is the length of DC?
Step 1: State the Angle Bisector Theorem
By the Angle Bisector Theorem, the angle bisector from a vertex divides the opposite side in the ratio of the two adjacent sides:
Step 2: Substitute the Known Values
Given AB=6 cm, AC=9 cm, and BD=4 cm, substituting into the ratio yields:
**Step 3: Solve for DC
Result
This theorem is essential for solving numerous geometry problems in competitive exams.
sin 30° = ?
This question tests your knowledge of standard trigonometric ratios for common angles.
Step 1: Recall the standard trigonometric ratios table for common angles (0°, 30°, 45°, 60°, 90°).
Step 2: Locate the value of sin30° from the standard table:
Step 3: Verify using the unit circle or right triangle approach — in a 30°-60°-90° triangle, the side opposite to 30° is half the hypotenuse, giving us:
Step 4: Convert the fraction to decimal form:
Therefore, sin30°=0.5.
Solve: 2x + 5 = 15
This is a linear equation problem where we need to isolate the variable x on one side.
Step 1: Start with the equation
Step 2: Subtract 5 from both sides to remove the constant term
Step 3: Divide both sides by 2 to isolate x
Step 4: Verify by substituting x=5 back into the original equation
Therefore, x=5.
Area of circle with radius 7cm (π=722)?
To find the area of a circle, we use the formula Area=πr2, where r is the radius.
Step 1: Write the formula for the area of a circle.
Step 2: Substitute the given values: radius r=7 cm and π=722.
Step 3: Calculate 72.
Step 4: Simplify by canceling 7.
Therefore, the area of the circle is 154 cm2.
Sum of angles in a triangle?
The sum of all three interior angles of any triangle is always constant, regardless of the triangle's shape or size.
Step 1: Understand the Fundamental Property
Every triangle has exactly 3 interior angles. These angles are formed where two sides of the triangle meet.
Step 2: Apply the Angle Sum Theorem
The angle sum property of a triangle states:
Step 3: Verify with Examples
This property holds for all triangles without exception. It is a foundational result in Euclidean geometry.
Therefore, the sum of the interior angles of a triangle is:
log₁₀(1000) = ?
The logarithm is the inverse operation of exponentiation; logb(x)=y means by=x.
Step 1: Understand what we need to find.
We need to find the value of log10(1000). This asks: "10 raised to what power equals 1000?"
Step 2: Express 1000 as a power of 10.
Step 3: Apply the logarithm definition.
Since 103=1000, we have:
Therefore, log10(1000)=3
f(x)=x²+3x+2. f(2)=?
To find f(2), substitute x=2 into the given function and calculate the result.
Step 1: Write the function.
Step 2: Substitute x=2 into the function.
Step 3: Calculate the square term.
Step 4: Calculate the multiplication term.
Step 5: Add all terms.
Therefore, f(2)=12
√144 = ?
The square root is the inverse operation of squaring, and asks: what number multiplied by itself equals 144?
**Step 1: Understand what 144 means**
We need to find a number that, when multiplied by itself, gives 144:
**Step 2: Check which number squared equals 144
We test candidates by squaring them:
Step 3: Verify the answer
Since 12×12=144, we conclude:
Therefore, the answer is 12.
Probability of head in coin toss?
When flipping a fair coin, the probability of any single outcome equals the number of favorable outcomes divided by the total number of possible outcomes.
Step 1: Identify the total possible outcomes when tossing a coin.
A coin has exactly 2 possible outcomes: Head or Tail.
Step 2: Identify the favorable outcomes for getting a Head.
Step 3: Apply the probability formula.
Step 4: Calculate.
Therefore, the probability of getting a Head in a coin toss is 21, or 0.5, or 50%.
Slope of y = 3x + 5?
The slope of a line is the coefficient of x in the standard linear equation form y=mx+c.
Step 1: Identify the standard form of a linear equation.
The equation of a line is written as:
where m is the slope and c is the y-intercept.
Step 2: Compare the given equation with standard form.
Step 3: Extract the slope.
Matching coefficients:
Therefore, the slope is 3.
HCF of 24 and 36?
The Highest Common Factor (HCF) is the largest number that divides both given numbers without leaving a remainder.
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Step 1: Find all factors of 24
Step 2: Find all factors of 36
Step 3: Identify the common factors
Step 4: Select the highest common factor
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Alternative Method — Prime Factorization
Taking the lowest power of each common prime factor:
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Conclusion:
cos 60° = ?
This question tests your knowledge of standard trigonometric values for common angles.
Step 1: Recall the standard angle values
The trigonometric ratios for 0°, 30°, 45°, 60°, and 90° are fixed values that must be memorized for competitive exams.
**Step 2: Identify cos60° from the standard table**
For 60°, the cosine value is:
Step 3: Verify using the unit circle concept
At 60°, if you place a point on the unit circle, the x-coordinate (which represents cosine) equals 21.
Step 4: Eliminate other options
Therefore,