42764.Two pipes can fill the cistern in 10hr and 12 hr respectively, while the third empty it in 20hr. If all pipes are opened simultaneously, then the cistern will be filled in
7.5 hr
8 hr
8.5 hr
10 hr
Explanation:
Work done by all the tanks working together in 1 hour.
$\\dfrac{1}{10}+\\dfrac{1}{12}−\\dfrac{1}{120}=\\dfrac{2}{15}$
Hence, tank will be filled in $\\dfrac{15}{2}$=7.5 hour
Work done by all the tanks working together in 1 hour.
$\\dfrac{1}{10}+\\dfrac{1}{12}−\\dfrac{1}{120}=\\dfrac{2}{15}$
Hence, tank will be filled in $\\dfrac{15}{2}$=7.5 hour
42765.Ram, Krish and Bhim can complete a work in 30 days. If Ram and Krish together can complete the same work in 40 days, then how long will Bhim take to complete it?
60
80
100
120
Explanation:
Ram + Krish + Bhim’s work = $\\dfrac{1}{30}$
Ram and Krish’s work= $\\dfrac{1}{40}$
Bhim’s work = $\\dfrac{1}{30}$- $\\dfrac{1}{40}$= $\\dfrac{1}{120}$
Ram + Krish + Bhim’s work = $\\dfrac{1}{30}$
Ram and Krish’s work= $\\dfrac{1}{40}$
Bhim’s work = $\\dfrac{1}{30}$- $\\dfrac{1}{40}$= $\\dfrac{1}{120}$
42766.30 labourers working 7 hours a day can finish a piece of work in 18 days. If the labourers work 6 hours a day, then the number of labourers required to finish the same piece of work in 30 days will be
15 days
21 days
25 day
22 day
Explanation:
That is, 1 work done = 30 × 7 ×18 = ? × 6 × 30
? (No. of labourers) = 30 × 7 × 18/6 × 30 = 21
That is, 1 work done = 30 × 7 ×18 = ? × 6 × 30
? (No. of labourers) = 30 × 7 × 18/6 × 30 = 21
42767.A certain number of men can do a work in 40days. If there were 8 men more, it could be finished in 10 days less. How many men were there initially?
30
24
16
20
Explanation:
Let ‘x’ be the initial number of men
Then, 1 work done = x × 40
Then, x × 40 = (x + 8 ) (40 – 10)
40x = 30x + 240
10x = 240
Therefore, x = 240/10 = 24 men.
Let ‘x’ be the initial number of men
Then, 1 work done = x × 40
Then, x × 40 = (x + 8 ) (40 – 10)
40x = 30x + 240
10x = 240
Therefore, x = 240/10 = 24 men.
42768.Mr. Ram is on tour and he has Rs 360 for his expenses. If he exceeds his tour by 4 days he must cut down daily expenses by Rs 3. The number of days of Mr. Ram s tour programme is
28 Days
24 Days
22 Days
20 Days
Explanation:
Let Ram under takes a tour of x days.
Then, expenses for each day = $\\dfrac{360}{x}$
$\\dfrac{360}{x+4}=\\dfrac{360}{x}-3$
x=20 and −24
Hence, x= 20 days.
Let Ram under takes a tour of x days.
Then, expenses for each day = $\\dfrac{360}{x}$
$\\dfrac{360}{x+4}=\\dfrac{360}{x}-3$
x=20 and −24
Hence, x= 20 days.
42769.If 4 men can colour 48 m long cloth in 2 days, then 6 men can colour 36 m long cloth in
1 days
1 ½ days
$\dfrac{3}{4}$ day
$\dfrac{1}{2} day
Explanation:
The length of cloth painted by one man in one day = 48 / 4 × 2 = 6 m
No. of days required to paint 36 m cloth by 6 men = 36/ 6 × 6 = 1 day.
The length of cloth painted by one man in one day = 48 / 4 × 2 = 6 m
No. of days required to paint 36 m cloth by 6 men = 36/ 6 × 6 = 1 day.
42770.2 men and 4 boys can complete a work in 4 days. 5 men and 6 boys can complete the same work in 3 days. The work done by 2 boys is equal to the work of how many men?
4
5
6
7
Explanation:
(2m + 4b)’s one day’s work = $\\dfrac{1}{4}$
(5m + 6b)’s one day’s work = $\\dfrac{1}{3}
=> (8m + 16b)’s one day’s work = (15m + 18b) ’s one day’s work
=> 7 men’s work = 2 boy’s work
(2m + 4b)’s one day’s work = $\\dfrac{1}{4}$
(5m + 6b)’s one day’s work = $\\dfrac{1}{3}
=> (8m + 16b)’s one day’s work = (15m + 18b) ’s one day’s work
=> 7 men’s work = 2 boy’s work
42771.If 3 persons can do 3 times of a particular work in 3 days, then, 7 persons can do 7 times of that work in
7 days
6 days
4 days
3 days
Explanation:
That is, 1 person can do one time of the work in 3 days.
Therefore, 7 persons can do 7 times work in the same 3 days itself.
That is, 1 person can do one time of the work in 3 days.
Therefore, 7 persons can do 7 times work in the same 3 days itself.
42773.There is enough provisions for 600 men in an army camp for 25 days. If there were 300 men less, how long will the provision last?
35 days
40 days
45 days
50 days
Explanation:
We have, M1D1 = M2D2
600*25= 300* D2
D2 = $\\dfrac{ 600*25}{300}$ = 50 days.
We have, M1D1 = M2D2
600*25= 300* D2
D2 = $\\dfrac{ 600*25}{300}$ = 50 days.
42774.Adam is thrice as good a workman as Brain and together they finish the piece of work in 15 days. In how many days will Adam alone finish the work?
20 days
35 days
15 days
40 days
Explanation:
Adam’s 1 day’s work: Brain’s 1 day’s work = 3 : 1
(Adam + Brain)’s 1 day’s work = 1/15
Now, divided 1/15 in the ratio 3 : 1
Therefore, Adam’s 1 day’s work = 1/15 × 3/4 = 1/20
Therefore, Adam alone can finish the work in 20 days.
Adam’s 1 day’s work: Brain’s 1 day’s work = 3 : 1
(Adam + Brain)’s 1 day’s work = 1/15
Now, divided 1/15 in the ratio 3 : 1
Therefore, Adam’s 1 day’s work = 1/15 × 3/4 = 1/20
Therefore, Adam alone can finish the work in 20 days.