Try each question on your own first. Use the Show Answer button only after you have selected your option, then read the explanation and revise the related concept from your chapter notes.
Explanation: All circles have the exact same shape regardless of their size, making them similar.
2. All squares are:
A. Congruent
B. Similar
C. Equal in perimeter
D. None of these
Answer: B. Similar
Explanation: All squares have corresponding angles equal to 90° and their side lengths are proportional, so they are similar.
3. All _______ triangles are similar.
A. Isosceles
B. Scalene
C. Equilateral
D. Right-angled
Answer: C. Equilateral
Explanation: Every equilateral triangle has internal angles measuring 60°, satisfying the similarity criterion.
4. Basic Proportionality Theorem is also known as:
A. Pythagoras Theorem
B. Thales Theorem
C. Euclid's Lemma
D. Apollonius Theorem
Answer: B. Thales Theorem
Explanation: Basic Proportionality Theorem (BPT) was introduced by the Greek mathematician Thales.
5. In ΔABC, DE || BC such that AD = 1.5 cm, DB = 3 cm, and AE = 1 cm. What is EC?
A. 1.5 cm
B. 2 cm
C. 2.5 cm
D. 3 cm
Answer: B. 2 cm
Explanation: By BPT, AD/DB = AE/EC ⇒ 1.5/3 = 1/EC ⇒ 1/2 = 1/EC ⇒ EC = 2 cm.
6. If two triangles are similar, then their corresponding sides are:
A. Equal
B. Proportional
C. Parallel
D. Perpendicular
Answer: B. Proportional
Explanation: By definition, two triangles are similar if their corresponding angles are equal and corresponding sides are in the same ratio (proportional).
7. If ΔABC ~ ΔPQR, then which of the following is true?
A. AB/PQ = BC/QR = AC/PR
B. AB/QR = BC/PR = AC/PQ
C. AB/PR = BC/PQ = AC/QR
D. AB = PQ
Answer: A. AB/PQ = BC/QR = AC/PR
Explanation: In similar triangles, the ratio of corresponding sides is equal: AB/PQ = BC/QR = AC/PR.
8. Which of the following is NOT a criterion for similarity of two triangles?
A. AAA
B. SAS
C. SSS
D. RHS
Answer: D. RHS
Explanation: AAA, SAS, and SSS are criteria for similarity. RHS is primarily a congruence criterion.
9. In ΔABC, DE || BC. If AD/DB = 3/5 and AC = 5.6 cm, then AE is equal to:
25. A guy wire attached to a vertical pole of height 18 m is 24 m long and has a stake attached to other end. How far from base of pole should stake be driven?
This page contains a chapter-wise objective practice set. Try the questions without checking the answer first, then use the explanation to understand the point you missed. The current page contains 30 questions, so you can practise in smaller sets when you are revising.
Quick revision tip
After the practice set, write down the question numbers you missed and revise only those concepts once more. This makes MCQ practice more useful than repeatedly attempting the same questions without reviewing mistakes.