En el numeral 87.684 la cifra de las decimas es la cifra de las centésimas es la cifra de las milésimas es la parte entera de la expresión decimas es en la parte entera, la cifra de unidades es , mientras que la cifra de la decena es

La cifra de las decimas es 6, la cifra de las centésimas es 8, la cifra de las milésimas es 4, y en la parte entera, la cifra de unidades es 7, mientras que la cifra de la decena es 8.

Step-by-step explanation:

Para responder la pregunta, se debe descomponer el número en cuestión:

87.684

8 = Indica la cantidad de decenas del número, es decir, 8 decenas (80).

7 = Indica las unidades dentro de la decena, es decir, 7 unidades más que 80.

.6 = Indica la cantidad de decenas del entero.

.08 = Indica la cantidad de centésimas del entero.

.004 = Indica la cantidad de milésimas del entero.

Así, la cifra de las decimas es 6, la cifra de las centésimas es 8, la cifra de las milésimas es 4, y en la parte entera, la cifra de unidades es 7, mientras que la cifra de la decena es 8.

step-by-step explanation:

30% of $420 is 0.30($420) = $126 and $420 + $126 = $546.

or, 130% of $420 is 1.3($420) = $546.

notice that this is not the $600 original list price with which we started.

why doesn't this work?

the method does not work because 30% of $420 is not the same amount as the 30% of $600. it may seem obvious when stated this way, but it is a very common error made on problems of this type. we cannot just use the same percent and get back to the original amount because we are taking that percent of a different value.

to work problems of this type correctly, it is generally best to write an equation for the situation and then solve.

example: since (100% – 30%)(original price) = (sale price)

70% of the   (original price) is $420.

0.7x   = 420

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x = 600

the original cost was $600.

we may also solve this problem using the two-step method. working the problem in two steps requires us to use more algebra skills. we have to know that x = 1x (identity property of multiplicationtext annotation indicator) and that 1x – 0.3x = 0.7x (subtracting like terms). then we solve the problem as follows:

(original price) – 30%(original price) = sale price

x – 0.3x = 420

0.7x = $420

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x = 600

the original cost was $600.  

note that with both of the above methods we do obtain the correct original amount.

example: after a 5% pay raise, hermione is earning $22,680 per year. what was she earning before the pay raise?

105% of (original salary) = current salary

1.05x = 22,680

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x = 21,600

hermione earned $21,600 per year before the pay raise.

this is an example so maybe you will get how to at least do it!