GATE Questions

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Let the cost price of the bottle = Rs. 100

Selling price of the bottle = Rs. 100 - Rs. 9 = Rs. 91

Then, from the given data,

=> 112 (1/2) - 91 = 15

=> 21 (1/2) = 15

=> 43 = 15

Then 100 = ?

1500/43 = 34.885 =~ 35

Hence, the cost price of the bottle = Rs. 35

The scientific study of rocks is called petrology, which is an essential component of geology.

A magnifying glass is a convex lens that is used to produce a magnified image of an object. It is also called a hand lens in laboratory contexts.

A number of possible explanations for why manhole covers are round include :

1. A round manhole cover cannot fall through its circular opening, whereas a square, rectangular, or oval manhole cover could fall in if it were inserted diagonally in the hole.

2. Circular covers don’t need to be rotated or precisely aligned when placing them on the opening.

3. A round manhole cover is easily moved and rolled.

4. Human beings have a roughly circular cross-section.

5. Round tubes are the strongest shape against the compression of the earth around them, so the cover of the tube would naturally be round as well.

6. It’s easier to dig a circular hole.

In rusting the Iron ore make a chemical reaction with the oxygen in the presence of water and environmental or atmospheric moisture to produce an Iron oxide. Iron oxide is otherwise called as rust.

The rusting of iron is a chemical change because it is two substances reacting together to make a new substance.