explain ratio and propotion lesson

In mathematics, a ratio is a relationship between two numbers of the same kind(e.g., objects, persons, students, spoonfuls, units of whatever identical dimension), expressed as "a to b" or a:b, sometimes expressed arithmetically as a dimensionlessquotient of the two that explicitly indicates how many times the first number contains the second (not necessarily an integer).

1. Proportions. Proportion says that two ratios (or fractions) are equal.