GUIDE TO MATHEMATICS, Multiplying Fractions math - Read the following information and then work on the guide that has been delivered. Multiply
: already seen the addition and subtraction with fractions. Third review multiplication.
In this operation, the first thing to do is simplify convieneque fractions everything possible, in a vertical or cross. Then multiply the numerators and denominators obtained the producto.Este will always be an irreducible fraction, because it already simplified.
If any factor is mixed or whole number, we reduce it to an improper fraction and then multiply:
simplify and reduce to a mixed number. Properties
As multiplication with cardinal numbers, multiplication of fractions also has the following properties:
have closure.
is commutative.
is associative.
Its neutral element to any fraction equal to integer 1, and as a fraction absorbing all an integer 0.
is distributive with respect to the addition of fracciones.A unlike the multiplication of cardinal numbers, fractions appears in a new building: The multiplicative inverse element, or inverse, is to multiply a fraction by another, so as to obtain the neutral element, which is the whole 1.For example, the multiplicative inverse:
9 / 5 = 5 / 9 result will be 1
Applications Working with fractions is very important to everyday life. In this context we can distinguish two very important applications of the multiplication of fractions.
a) The multiplication of fractions allows us to calculate the number or fraction of a fraction of another fraction. For that we need only multiply the data.
studied two cases:
1)
if we calculate the 5 / 8 of 24 people, multiply 5 x 24 and the result is divided by 24 5 x 24 = 120 120: 8 = 15
score: 15 people. 2) if we calculate the 7 / 10 of 20/21 for 7 simplify
7: 7 = 1 and 21: 7 = 3 10: 10 = 1 and 20: 10 = 2 then multiply 1 / 1 x 2 / 3 = 2 / 3
score 2 / 3
b) multiplying fractions allows us to calculate percentages.
Percentages are fractions with denominator 100. So if, for example, say that 60% (percent) of students have siblings guys, it means that every 100 students, 60 comply with this would be estacondición.Escrito as a fraction: 60/100
In the situation-as second example, having to calculate the 30% of the 600 employees at a factory, just apply multiplication:
30 x 600 and the result is divided by 100
30 x 600 = 18 000 18 000 100 = 180
Results 180 employees.
