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The average weight of A, B and C is 45 kg, that of A and B is 40 kg and B and C is 43 kg. What is the weight of B?
Question:
The average weight of A, B and C is 45 kg, that of A and B is 40 kg and B and C is 43 kg. What is the weight of B?
Choose the correct answer:
- A. 17 kg
- B. 26 kg
- C. 20 kg
- D. 31 kg ✅ Correct
Explanation:
Weight of A+B+C = 45 × 3 = 135 kg .....(i)
Wt. Of A+B = 40 × 2 = 80 kg .....(ii)
Weight of B + C = 43 × 2 = 86 kg ......
(iii)
Now on adding (ii) and (iii),
wt. of A+2B+C = 166kg
A+B+ C = 135 kg ....given (i)
On Subtracting (i)
B = 31 kg ..Ans
Weight of A+B+C = 45 × 3 = 135 kg .....(i)
Wt. Of A+B = 40 × 2 = 80 kg .....(ii)
Weight of B + C = 43 × 2 = 86 kg ......
(iii)
Now on adding (ii) and (iii),
wt. of A+2B+C = 166kg
A+B+ C = 135 kg ....given (i)
On Subtracting (i)
B = 31 kg ..Ans
Related Questions & One-Liners
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Related MCQs
The average of following 5 numbers is 8, find the missing number in 7, 5, 3,12,?.
Explanation:
The sum of all numbers = 8 × 5 = 40
So, ? = 40 - (7+3+12+5) = 13 Ans.
The sum of all numbers = 8 × 5 = 40
So, ? = 40 - (7+3+12+5) = 13 Ans.
The average of the first three numbers is double of the fourth number. if the average of all the four numbers is 12, find the 4th number.
Explanation:
Let the 4th number be x,
Then the average of first three numbers = 2x ,
So the sum of first 3 numbers = 2x × 3 = 6x,
Since the average of 4 numbers = 12.
Then sum of 4 numbers = 12 × 4 = 48.
so, 48 - 6x = x => 7x = 48,
x = 48/7 ..Ans.
Let the 4th number be x,
Then the average of first three numbers = 2x ,
So the sum of first 3 numbers = 2x × 3 = 6x,
Since the average of 4 numbers = 12.
Then sum of 4 numbers = 12 × 4 = 48.
so, 48 - 6x = x => 7x = 48,
x = 48/7 ..Ans.
If 3 men and 4 boys complete a work in 7 days and 2 men and 3 boys do the same work in 10 days . In
Explanation:
In an election between two candidates 10% voters doesn’t cast their votes and 85 votes were de
Explanation:
Lets take total votes =100% 10%doesn’t cast their votes So, (100-90) = 90% cast their votes. total valid votes = 90% -85 one candidate get 50% of votes of voters list. So, other candidate get = (90% - 85 )-50%= 40% - 85 so ,50 % - (40% - 85) = 165 50% - 40% + 85 = 165 10% = 80 100 % = 800 So total voters is 800
Lets take total votes =100% 10%doesn’t cast their votes So, (100-90) = 90% cast their votes. total valid votes = 90% -85 one candidate get 50% of votes of voters list. So, other candidate get = (90% - 85 )-50%= 40% - 85 so ,50 % - (40% - 85) = 165 50% - 40% + 85 = 165 10% = 80 100 % = 800 So total voters is 800
A Trader Who Marks His Good Upto 50% And Offered Discount Of 20% . What % Profit The Trade Makes After Offering The Payment?
Explanation:
Sol. Let cp = 100, MRP = 150
\( sp = 150 \times {80 \over 100} \)
\( = Rs. 120 \)
Hence, Profit = 20%
[short trick:]
By successive formula
\( x+y+{xy \over 100} \)
\( 50-20+{50 \times (-20) \over 100} \)
30 – 10 = 20%
Sol. Let cp = 100, MRP = 150
\( sp = 150 \times {80 \over 100} \)
\( = Rs. 120 \)
Hence, Profit = 20%
[short trick:]
By successive formula
\( x+y+{xy \over 100} \)
\( 50-20+{50 \times (-20) \over 100} \)
30 – 10 = 20%
What number has 5 to 1 ratio to the number 10?
Explanation:
Given, ratio is 5 : 1 that means antecedent is 5 times greater than the consequent.
Given consequent = 10, so the number is 10 × 5 = 50 answer.
Given, ratio is 5 : 1 that means antecedent is 5 times greater than the consequent.
Given consequent = 10, so the number is 10 × 5 = 50 answer.
There are 120 students in a picnic tour, if ratio of girls and boys is 5 : 7 then how many boys are in this tour?
Explanation:
Given ratio of girls : boys = 5 : 7 = 5/7
multiplying the antecedent and consequent by the same number, let by x,
girls = 5x, and boys = 7x
total = 120;
as par given 5x + 7x = 120
=> x = 120/12 = 10
hence, girls = 5 × 10 = 50
and Boys = 7 × 10 = 70 answer
Given ratio of girls : boys = 5 : 7 = 5/7
multiplying the antecedent and consequent by the same number, let by x,
girls = 5x, and boys = 7x
total = 120;
as par given 5x + 7x = 120
=> x = 120/12 = 10
hence, girls = 5 × 10 = 50
and Boys = 7 × 10 = 70 answer
in 3 : 5 , here 3 is
Explanation:
in a ratio the first term is called antecedent and the second term is called consequent. in 3 : 5, 3 is antecedent and 5 is consequent, means and extremes are terms used in case of proportion
i.e. 1 : 2 :: 2 : 4, here 1 and 4 are extremes and 2 and 2 are means.
in a ratio the first term is called antecedent and the second term is called consequent. in 3 : 5, 3 is antecedent and 5 is consequent, means and extremes are terms used in case of proportion
i.e. 1 : 2 :: 2 : 4, here 1 and 4 are extremes and 2 and 2 are means.
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