Ratio: How much of one thing compared to the other.
But we have got two different types of definitions of Proportions:
How much of one thing is compared to the total.
Proportion says two ratios are equal.
And sometimes I see people using the words ratio and proportion alternatively.
As I am a basic mathematics learner I am totally confused.
Please help me understand the two concepts.
Thanks in advance.
The ratio of any number of quantities is a quantitative comparison of their measures.
In particular, the binary ratio $T:H$ is equivalent to the fraction $\displaystyle\frac TH.$
On the other hand, direct proportion equates ratios of corresponding values.
For example, variables $T$ and $H$ being in (direct) proportion means that as they vary, $$\frac {T_i}{H_i}\equiv \frac {T_1}{H_1}=\frac {T_2}{H_2}=\frac {T_3}{H_3};$$ in other words, the pairs of corresponding values $(T_i,H_i)$ are in (direct) proportion.
Variables $T$ and $H$ being in inverse proportion means that as they vary, $$T_iH_i\equiv T_1H_1=T_2H_2=T_3H_3.$$
In less technical contexts, a “proportion” of a quantity is a proper fraction or percentage smaller than $100\%.$