maths SA-1 question paper and answers

MATHS-SA1-TEST1

Q1)

Use the following information to answer the next question.
The steps for finding the H.C.F. of 2940 and 12348 by Euclid’s division lemma are as follows.
12348 = a × 4 + b a = b × 5 + 0
What are the respective values of a and b?
A.
2352 and 588
B.
2940 and 588
C.
2352 and 468
D.
2940 and 468
Answer
The steps to find the H.C.F. of 12348 and 2940 are as follows.
12348 = 2940 × 4 + 588
2940 = 588 × 5 + 0
Comparing with the given steps, we obtain a = 2940 and b = 588
Thus, the value of a and b are 2940 and 588 respectively.
The correct answer is B.

Q2)

Use the following information to answer the next question.
The given figure shows the graph of polynomial, p(x) = x2 + kx − 15

What is the value of k?
A.
3
B.
2
C.
−2
D.
−3
Answer
In the given figure, the graph intersects x-axis at two points, (−3, 0) and (5, 0). Therefore, x = −3 and x = 5 are the zeroes of the polynomial p(x).
Substituting x = 5 in p(x), we obtain p(5) = (5)2 + k(5) − 15 = 0
⇒ 25 + 5k − 15 = 0
⇒ 5k = −10
⇒ k = −2
Thus, the value of k is −2.
The correct answer is C. Q3)

If the pair of linear equations, 7x + k1y = 2 and k2x + 2y = 3, has a unique solution, then which of the following relations is always correct?
A.
kl ≠ 2 and k2 ≠ 7
B.
klk2 ≠ 9
C.
klk2 ≠ 14
D.
k1 ≠ 7 and k2 ≠ 2
Answer
We know that the pair of equations, and , will have a unique solution if .
7x + k1y = 2 and k2x + 2y = 3 will have a unique solution if

7 × 2 ≠ kl k2 kl k2 ≠ 14
Thus, the relation given in alternative C is correct.
The correct answer is C. Q4)

Which of the following relations is correct for the three measures of central tendency?
A.
Median = Mode + 2 Mean
B.
3 Median = Mode − 2 Mean
C.
Mode = 3 Median − 2 Mean
D.
3 Mode = Median + 2 Mean
Answer
The relation between the three measures of central tendency is given by,
3 Median = Mode + 2 Mean
⇒ Mode = 3 Median − 2 Mean
The correct answer is C.