30 workers can build a house in 20 days. 10 days after beginning the work, it was stopped for 6 days due to bad weather. How many extra workers will be needed to finish the work on time ?

Which is the twice divided ratio of 4 : 9 ?

What is the value of second quantity is successive ratio of 4 : 3 and 5 : 6?

A banana seller bought bananas at the rate of Tk. 25 per four bananas and sold at the rate of  Tk. 27. He gained Tk. 50 as profit. How many bunches of four bananas did he buy?

What is the successive ratio of 5 : 3 and 2: 5 ?

30 metre cloth are distributed among Maisa, Maria and Tania in the ratio 5 : 3 : 2.  How many metre of cloth did Maisa get ?

Which one is the fourth proportional of 3, 5. 15 ?

If A : B = 4 : 7 and B : C = 10 : 7, what is the value of C : B : A ?

30 metre cloth are distributed among Maisa, Maria and Tania in the ratio 5 : 3 : 2.  How many metre of cloth did Maria get more than Tania ?

A shopkeeper bought a match box at Tk. 1.50 and sold at Tk. 2.00. What is the percentage of profit ?