Answer: 26

Explanation:
Let the number of hens be x and the number of cows be y.
Then, x + y = 48 .... (i)
and 2x + 4y = 140 x + 2y = 70 .... (ii)
Solving (i) and (ii) we get: x = 26, y = 22.
The required answer = 26.

Answer: 175

Explanation:
Suppose the man works overtime for x hours.
Now, working hours in 4 weeks = (5 x 8 x 4) = 160.
160 x 2.40 + x x 3.20 = 432
3.20x = 432 - 384 = 48
x = 15.
Hence, total hours of work = (160 + 15) = 175.

Answer: 30 birds

Explanation:

Answer: 100

Explanation:
Let the number of students in rooms A and B be x and y respectively.
Then, x - 10 = y + 10 x - y = 20 .... (i)
and x + 20 = 2(y - 20) x - 2y = -60 .... (ii)
Solving (i) and (ii) we get: x = 100 , y = 80.
The required answer A = 100.

Answer: Rs. 3900

Explanation:

Answer: 1600

Explanation:
Let Peter’s share be x.
Hence, David gets x/4 and Alex gets x/2.
x + x/4 + x/2 = 2800
7x/4 = 2800
x = Rs.1600

Answer: 5000

Explanation:
Let x amount be the total money declared in the will.
Hence, x/2 is the amount that goes to the wife. Of the remaining (i.e. x/2), 4/5th is shared among 4 sons. The share received by each son is Rs.25000.
(x/2) *(4/5)/4 = 25000
(x/2) *(4/5) = 1,00,000
x*(2/5) = 1,00,000
x= 2,50,000
Now, 1/5th of x/2 is shared by 5 daughters
= 1/5 * 250000/2 = 25000
Hence, each daughter gets Rs.5000.

Answer: 48 minutes

Explanation:
Total time a student spends in college = 4 hours 20 minutes = 260 minutes
As there are 5 lectures, the number of breaks between lectures is 4. Total time of the break = 20 minutes
Hence, the duration of each lecture is = (260 – 20)/5
= 48 minutes

Answer: 1/3

Explanation:
Out of every 5 women invited only 2 attended the ceremony.
Similarly, out of every 4 men invited, only 1 attended the ceremony.
Hence, out of every 9 people invited only 3 attended the ceremony = 3/9 = 1/3.

Answer: 321

Explanation:
Let the number of rows be x, number of trees in each row be x.
(x)(x) = x2 = 103041,x=321