Ratio: the quotient of the former item divided by the latter item is called ratio.
The nature of the ratio: the first term and the second term of the ratio are multiplied or divided by the same number at the same time (except zero), and the ratio remains unchanged.
Proportion: Two expressions with equal proportions are called proportions. A:b=c:d or
The essence of proportion: the product of two external terms is equal to the product of two internal terms (cross multiplication), and ad=bc.
Positive proportion: If A is expanded or reduced several times, B is also expanded or reduced several times (when the quotient of AB remains unchanged), A is in direct proportion to B. ..
Inverse ratio: If A expands or contracts several times, B also contracts or expands several times (when the product of AB remains unchanged), A and B are inversely proportional.
Scale: The ratio of the distance on the map to the actual distance is called the scale.
Proportional distribution: dividing several numbers into several parts according to a certain proportion, which is called proportional distribution.
Extended data
The significance of 1 and ratio
Division of two numbers is also called the ratio of two numbers.
":"is a comparative symbol, pronounced "than". The number before the comparison symbol is called the first item of comparison, and the number after the comparison symbol is called the last item of comparison. The quotient obtained by dividing the former term by the latter term is called the ratio.
Compared with division, the former term of ratio is equivalent to dividend, the latter term is equivalent to divisor, and the ratio is equivalent to quotient.
The ratio is usually expressed in fractions, decimals and sometimes integers.
The last term of the ratio cannot be zero.
According to the relationship between fraction and division, the former term of ratio is equivalent to numerator, the latter term is equivalent to denominator, and the ratio is equivalent to fractional value.
2, the meaning of proportion
Two expressions with equal ratios are called proportions.
The four numbers that make up a proportion are called proportional terms.
The two items at both ends are called external items, and the two items in the middle are called internal items.
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