Question

How do you find out how many feet are in a mile?

Answer 1

Hint: The mile is an English unit of length of linear measure equal to 1,760 yards and standardized as exactly 1,609.344 meters by international agreement in 1959.
1 foot equals 30.48 cm, which can be taken to be 30.5 for small lengths, the difference between the two values being of the order of 2 cm for lengths close to 6 feet.
Another way to do the calculation would be to know that 1 yard is equal to 3 feet.

Complete step-by-step answer:
Let us use the meter scale to find the number of feet in a mile. There are 1,609.344 meters or 160,934.4 cm in 1 mile. We also know that 1 feet is equal to 30.48 cm.
Therefore, 160,934.4 cm are equal to $\dfrac{160,934.4}{30.48}$ = 5280 feet, which is the required value.
It can be noted that since 1 yard is 3 feet and there are 1,760 yards in 1 mile, the number of feet in a mile are equal to 1,760 × 3 = 5280 feet.

Note: The French revolution (1789 - 99) provided an opportunity for the French to reform their unwieldy and archaic system of many local weights and measures.
The units of the metric system, originally taken from observable features of nature, are now defined by seven physical constants being given exact numerical values in terms of the units. In the modern form of the International System of Units (SI), the seven base units are: meter (m) for length, kilogram (kg) for mass, second (s) for time, ampere (A) for electric current, kelvin (K) for temperature, candela (cd) for luminous intensity and mole for amount of substance. These, together with their derived units, can measure any physical quantity. Derived units may have their own unit name, such as the watt $\left( \dfrac{J}{s} \right)$ and lux $\left( \dfrac{cd}{{{m}^{2}}} \right)$ , or may just be expressed as combinations of base units, such as velocity $\left( \dfrac{m}{s} \right)$ and acceleration $\left( \dfrac{m}{{{s}^{2}}} \right)$ .