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- Question
- If nC r - 1 = 36, nC r = 84 and nC r + 1 = 126 then?
Options- A. n = 8, r = 4
- B. n = 9, r = 3
- C. n = 7, r = 5
- D. None of these
- Correct Answer
- n = 9, r = 3
ExplanationnCr - 1 = 36, nCr = 84 and nCr + 1 = 126
? nCr / nCr - 1 = 84/36
? 3n - 10r + 3 = 0 ....(i)
nCr + 1 / nCr = 126/84
? 2n - 5r - 3 = 0 .............(ii)
From (i) and (ii) r = 3, n = 9 - 1. 198.995 x 12.005 + 16.25 x 6.95 =?
Options- A. 2580
- B. 2550
- C. 2400
- D. 2500 Discuss
- 2. The face value of 8 in the numeral 458926 is?
Options- A. 8000
- B. 8
- C. 1000
- D. 458000 Discuss
- 3. 6, 9, 15, 21, 24, 28, 30?
Options- A. 25
- B. 21
- C. 24
- D. 30 Discuss
- 4. 6674 x 625 =?
Options- A. 4170160
- B. 4072360
- C. 4171050
- D. 4171250 Discuss
- 5. If ax + by = 6, bx ? ay = 2 and x 2 + y 2 = 4, then the value of ( a 2 + b 2) would be :
Options- A. 10
- B. 2
- C. 4
- D. 5 Discuss
- 6. What if the probability of getting a king or a queen in a single drawn from a pack of 52 cards?
Options- A. 1/26
- B. 1/13
- C. 2/13
- D. None of these Discuss
- 7. Find the 4th proportional to 4 , 16 and 7 ,
Options- A. 28
- B. 29
- C. 22
- D. 25 Discuss
- 8. Raj sold an item for ? 6384 and incurred a loss of 30%. At what price should he have sold the item to have gained a profit of 30%
Options- A. ? 14656
- B. ? 11856
- C. ? 13544
- D. cannot be determind Discuss
- 9. (2/3) x (6/8) x (2/3) x (3/4) =?
Options- A. 0.25
- B. 0.5
- C. 1.45
- D. 11.8 Discuss
- 10. The HCF and LCM of two natural numbers are 12 and 72, respectively. What is the difference between the two numbers, if one of the number is 24?
Options- A. 12
- B. 18
- C. 21
- D. 24 Discuss
More questions
Correct Answer: 2500
Explanation:
? = 198.995 x 12.005 + 16.24 x 6.95
= 199 x 12 +16 x 7 = 2388 + 112 = 2500
Correct Answer: 8
Explanation:
The face value of 8 in 458926 is 8
Correct Answer: 25
Explanation:
Each of the number except 28, is a multiple of 3.
Correct Answer: 4171250
Explanation:
6674 x 625 = 6674 x (5)4
= 6674 x (104/24
= 66740000/16 = 4171250
Correct Answer: 10
Explanation:
As we know that given in question,
ax + by = 6 ........................ (i)
bx ? ay = 2 ........................ (ii)
On squaring the both equation and adding,
a2 x2 + b2 y2 + 2abxy + b2 x2 + a2 y2 ? 2abxy = 36 + 4
? x2 (a2 + b2) + y2 (a2 + b2) = 40
? (a2 + b2) (x2 + y2) = 40
As per given question, x2 + y2 = 40 , Put this value in above equation, we will get
? (a2 + b2) × 4 = 40
? a2 + b2 = 10
Correct Answer: 2/13
Explanation:
Clearly, n (S) = 52, there are 4 kings and 4 queens
? P(E) = n (E) / n (S) = 8/52 = 2/13
Correct Answer: 28
Explanation:
Lat the 4th proportional = N
Then, 4 : 16 : : 7 : N
? 4/16 = 7/N
? 4N = 7 x 16
? N = (7 x 16)/4 = 7 x 4 = 28
Correct Answer: ? 11856
Explanation:
CP = 100/70 = x 6384 = ? 9120
To gain 30%, SP = 130% of 9120
SP = (130/100) x 9120 = ? 11856
Correct Answer: 0.25
Explanation:
(2/3) x (6/8) x (2/3) x (3/4) = 1/4 = 0.25
Correct Answer: 12
Explanation:
Second number = (LCM x HCF) / first number
= (72 x 12)/ 24 = 36
Difference between the two numbers
= 36 - 24 = 12
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