Q. 141. Which of the following two angles can be classified as complementary angles:
(A) and
(B) and
(C) and
(D) and
Answer:
(C) and
Explanation:
Two angles are considered complementary if their sum equals exactly . Here, .
Q. 142. A square and a rhombus are always:
(A) Similar
(B) congruent
(C) similar but not congruent
(D) neither similar nor congruent
Answer:
(D) neither similar nor congruent
Explanation:
Both shapes share the property of having four equal sides. However, a square is strictly defined by having four $90^{\circ}$ angles. A general rhombus does not necessarily have $90^{\circ}$ angles, meaning their internal angles can differ, making them neither inherently similar nor congruent.
Q. 143. In a rectangle if the length is 8 cm and the breadth is 6 cm, then the diagonal = ?
(A) 9 cm
(B) 14 cm
(C) 10 cm
(D) 12 cm
Answer:
(C) 10 cm
Explanation:
Using the Pythagorean theorem: Diagonal cm.
Q. 144. 30th term of the Arithmetic Progression 10, 7, 4,… is:
(A) 97
(B) 77
(C) -77
(D) -87
Answer:
(C) -77
Explanation:
The first term , and the common difference . The 30th term is calculated as .
Q. 145. A train travels 360 km at a uniform speed. If the speed had been $5~km/h$ more, it would have taken one hour less for the same journey. What was the original speed of the train?
(A)
(B)
(C)
(D)
Answer:
(B)
Explanation:
Let original speed be $v$. Time difference: . Solving this fractional equation yields . Factoring gives . Thus, .
