Solution:

3 lbs.

Explanation:
Based on information provided, we can deduce that
3/4 lbs = 1/4 of soap weight
=> soap weight = 4 x 3/4 = 3 lbs

Solution:

It can be done as shown below.

Explanation:
Grey line indicate the original position and green line indicate the new position of the toothpicks.

Solution:

Image C

Explanation:
If we add one matchstick to any other image, it forms a full-length capital letter.

Solution:

It can be done as shown in the picture below.

Solution:

We have removed two matchsticks and new equation formed is :

5 - 4 = 1.

Solution:

Puzzle solved as shown in pic below

Solution:

Yes, show in below picture

Solution:

Explained in picture below

Solution:

If you look at the answer figure, you will see four 1x1 squares and one 4x4 square. Nobody asked you to make five 1x1 squares. Most of the people get stuck at that.

Solution:

The image that we have attached here is self-explanatory. You just have to move four matches and you can obtain this figure.