An alloy of copper and aluminum has 40% copper. Another alloy of Copper and Zinc has Copper and Zinc in the ratio 2: 7. These two alloys are mixed in ratio 5:3. Quantity of aluminum is what percent more/less than the quantity of copper in final alloy.

Two boats, travelling at 5 Km/h and 10 Km/h respectively, head directly towards each other. They are now at a distance of 20 km from each other. How far apart are they (in Kms) one minute

before they collide? 

If the volume and curved surface area of a cylinder 616 𝐦𝟑 and 352m2 respectively, what is the total surface area of the cylinder (in 𝐦𝟐)?

In an alloy, zinc and copper are in the ratio 1 : 2. In the second alloy the same elements are in the ratio 2 : 3. In what ratio should these two alloys be mixed to form a new alloy in which the two elements are in ratio 5 : 8?

A boat travel 75 km downstream and take same time as it travels 60 km in upstream. Speed of boat in downstream is what percent of the speed of boat in still water.

A tank can be filled with water by two pipes A and B together in 36 minutes. If the pipe B was closed after 30 minutes, the tank is filled in 40 minutes. The pipe B can alone fill the tank in?

117.5, 117, 119, 111, 143, ?

25.6% of 250 +√ ? = 119