A ratio is characterised as a tool used to analyse the size of at least two values with respect to each other. We can use ratios to increase and decrease quantities and keep the proportions the same.

Speed, distance and time problems are interesting because they often describe simple situations which people confuse with the wrong formulas. It is also important that in these types of questions, the objects move at constant or average speeds in speed, distance and time scenarios.

There are two ways of telling the time: The 12-hour clock runs from midnight (12:00) to midnight.The $$24$$-hour clock uses the numbers 00:00 to 23:59.

The ratio of a set of numbers is a tool used in comparing two or more values. Sometimes we need to compare two quantities of the same type. So, the comparison by division method makes calculation easier than comparing by finding out the difference.

A proportion is a statement in which two or more ratios are equivalent to each other. There are two types of proportions: direct and inversly proportionate.

Inverse proportions describes the relationship where when one thing gets bigger, something else gets smaller. For instance, the alarm of an ambulance becomes louder as it approaches you and calmer as it goes farther away. That means if the distance between you and the ambulance is small, then the sound of the alarm of the ambulance heard will be loud.