Advantages and disadvantages of simple interest

Interest is the compensation received for lending money and paid by the person borrowing the money. A well-known form is the interest that consumers receive (credit or savings interest) or pay (debit interest) on an account at a bank.

There are essentially two types of interest, simple interest and compound interest. Simple interest is that which is not added to the initial capital, that is to say, the interests are always calculated on the same initial amount of the investment; while compound interest is one in which the profit obtained is added to the capital, generating increasing rates of profit since the interest percentage is calculated on a higher basis.

The main disadvantage of the simple interest is precisely that the base of obtaining gains is never widened, since the interests are not linked to the capital, with which a long-term investment with this type of interest is inadvisable. Now, the main advantage of this type of interest is that it allows you to quickly consolidate earnings, since you can withdraw the income obtained without modifying the base amount on which the interest is calculated.

where is the option given

you are playing an adventure game on your computer. you come across a troll who won't let you pass and there is no other way to get to the other side of the river except over the bridge he is guarding.

the troll is a nerd. he takes great delight in watching people struggle with his problems. very few get them. he only gives you one chance and then he changes the puzzle. you have to solve this one.

before you are four blocks. they are numbered 11,6, -7,21.

he tells that the answer he wants is minus and between -1 and - 2. you can use +, -, ×, ÷   ( and ) as many times as you like or no times at all. you don't like the way he's looking at you, but you need to cross the bridge. what do you do?