## Chapter 7: True or False (Pinocchio)

The computer is like a truth machine: you can ask it something and it will tell you whether it is true or false.

Unlike Pinocchio, the computer never lies.

# True or false?

When you write a statement to the computer, the computer answers you by `true`

or `false`

:

`true`

means that your statement is true`false`

means that your statement is false

Today, we are going to learn about three kind of statements:

`=`

: a statement that two things are equal`>`

: a statement that the first thing is greater than the second thing`<`

: a statement that the first thing is less than the second thing

For instance, it is true that `2`

and `2`

equals `4`

:

```
(= (+ 2 2) 4)
```

It is also true that `7`

times `8`

is `56`

:

```
(= (* 7 8) 56)
```

But it is false that `5`

times `6`

is `31`

:

```
(= (* 5 6) 31)
```

Can you modify the statement above and make it true?

It is true that `5`

times `7`

is greater than `10`

:

```
(> (* 5 7) 10)
```

But it is false that `2`

times `2`

is greater than `100`

:

```
(> (* 2 2) 100)
```

Can you modify the statement above and make it true?

# Exercises

A. Ask the computer if it is true that `7`

times `6`

equals `40`

:

```
()
```

You should get `false`

.

B. Is it true that `5`

and `7`

is less than `13`

?

```
()
```

You should get `true`

.

C. Is it true that `3`

times `4`

is `12`

?

```
()
```

You should get `true`

.

D. Is it true that `3`

times `6`

equals `10`

and `8`

?

```
()
```

You should get `true`

.

E. Is it true that `7`

times `7`

is greater than `10`

times `6`

?

```
()
```

You should get `false`

.

Send us a screenshot with your programs to viebel@gmail.com.