Mixed Questions
1. Problem: Solve for $m$ in the equation $42m - 1 = 64$.
Step 1: Add 1 to both sides: $42m = 65$.
Step 2: Divide both sides by 42: $m = \frac{65}{42} \approx 1.55$.
Answer choices do not include this value; likely a typo in options.
2. Problem: Find $a$ if $\sqrt{32} = 2$.
Step 1: $\sqrt{32} = 4\sqrt{2} \approx 5.66$, not 2.
Step 2: Possibly a typo; if $\sqrt{a} = 2$, then $a = 4$.
Answer: (b) 4.
3. Problem: Solve $4m m = 1$ (assuming $4m \times m = 1$ or $4m^2=1$).
Step 1: $4m^2 = 1$.
Step 2: Divide both sides by 4: $m^2 = \frac{1}{4}$.
Step 3: Take square root: $m = \pm \frac{1}{2}$.
Answer choices: closest is (a) -1, (b) 0, (c) 1, (d) 4; none match exactly.
4. Problem: Evaluate statements about exponents:
(i) $a^0 = 1$ (true for $a>0$),
(ii) $x^0 = y$ when $ax = ax$ (ambiguous, likely false),
(iii) $a^n = \frac{1}{a^n}$ (false, should be $a^{-n} = \frac{1}{a^n}$).
Correct: (a) i and ii (if ii is true), (b) i and iii (iii false), (c) ii and iii (both false), (d) i, ii and iii (false).
Answer: (a) i and ii.
5. Problem: Evaluate logarithm properties:
(i) $\log_a(MN) = \log_a M + \log_a N$ (true),
(ii) $\log_a 1 = 0$ when $a \neq 1$ (true),
(iii) If $a^x = N$ then $x = \log_a N$ (true).
Answer: (d) i, ii and iii.
6. Given $\log x = 3$, $\log y = 2$, find $\log_a (xy)$.
Step 1: $\log_a (xy) = \log_a x + \log_a y = 3 + 2 = 5$.
Answer: (c) 5.
7. Question incomplete; assuming find $\log_a (\frac{x}{y})$.
Step 1: $\log_a (\frac{x}{y}) = \log_a x - \log_a y = 3 - 2 = 1$.
Answer: (a) 1.
8. Problem: Distance from center to point on circle is called?
Answer: (c) Radius.
9. In circle with center O, AB is chord, OM perpendicular to AB.
(i) $AM = BM$ (true, perpendicular bisector),
(ii) $\angle OMB = \angle OMA$ (true, right triangles),
(iii) $OM = \frac{1}{2} AB$ (false).
Answer: (a) i and ii.
10. If two chords bisect each other, intersection point is?
Answer: (c) Inside the circle.
11. Angle subtended by diameter of circle is?
Answer: (b) Right angle.
12. Angle inscribed in tangential arc of circle?
Answer: (c) Right angle.
13. Max common tangents between two circles?
Answer: (d) 4.
14. Two circles with radii 10 cm and 5 cm touch each other.
Distance between centers = sum of radii = 15 cm.
Options do not include 15 cm; possibly error.
15. Given angle between OA and OB is 35°, find $\angle AOB$.
Answer: (b) 145° (assuming supplementary angle).
16. Given $PO=13$ cm, $OB=5$ cm, find $PA$.
Using Pythagoras: $PA = \sqrt{PO^2 - OB^2} = \sqrt{169 - 25} = \sqrt{144} = 12$ cm.
Answer: (b) 12 cm.
17. Ratio 3:5, common denominator 4, find LCM.
LCM of 3 and 5 is 15.
Answer: (b) 15.
18. Given $x:y=7:5$, $y:z=5:7$, find $x:z$.
Step 1: $x:z = 7:7 = 1:1$.
Answer: (b) 7:7.
19. Problem unclear; insufficient data.
20. Side length reduced by 10%, new side = 0.9 original.
Area reduced by $1 - 0.9^2 = 1 - 0.81 = 0.19 = 19\%$.
Answer: (b) 19%.
21. Ratio of area of circle to inscribed square.
Area circle = $\pi r^2$, area square = $(\sqrt{2}r)^2 = 2r^2$.
Ratio = $\frac{\pi r^2}{2 r^2} = \frac{\pi}{2}$.
Answer: (b) $\pi:2$.
22. Mangoes divided in ratio $1:1: \frac{1}{2} 5 9$ unclear; assuming ratio $1:1:\frac{1}{2}$.
Sum parts = $1 + 1 + 0.5 = 2.5$.
Mangoes = 146.
First brother gets $\frac{1}{2.5} \times 146 = 58.4$ approx.
Closest answer: (c) 45.
23. Proportion statements:
(i) $a:b = b:a$ then $a=b$ (false),
(ii) $a:b = c:d$ then $ad=bc$ (true),
(iii) $a:b=5:3$ then $a:5 = b:3$ (true).
Answer: (c) ii and iii.
24. Range 110, class number 10, class gap = $\frac{110}{10} = 11$.
Answer: (b) 11.
25. Serial number required in:
(i) median (true),
(ii) drawing straight line (false),
(iii) determining abundance (true).
Answer: (b) i and iii.