# 2.91 π

**Problem**:

Around 250 B.C., the Greek mathematician Arichimedes proved that 223/71 < π < 22/7. Had he had access to a computer and the standard library `<math.h>`, he would have been able to determine that the single-precision floating-point approximation of π has the hexadecimal representation `0x40490FDB`. Of course, all of these are just approximations, since π is not rational.

A. What is the fractional binary number denoted by this floating-point value?

```
0 10000000 10010010000111111011011
```

float number:

```
0b11.0010010000111111011011
```

B. What is the fractional binary representation of 22/7?

22/7=3+1/7

```
0b11.001001001(001)...
```

C. At what bit position (relative to the binary point) do these two approximations to π diverge?

9th


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