easy fraction problem, just want to double check!

Question

yolomcswagginsggg · Answer

?

girlgoyleh. · Answer

$$-4\div \frac{ 2 }{ 5 }$$

girlgoyleh. · Answer

i dont know how, but i got -10?? that doesnt make sense does it?

yolomcswagginsggg · Answer

−0.4

yolomcswagginsggg · Answer

or -2/5

girlgoyleh. · Answer

how did you get that

yolomcswagginsggg · Answer

A piece of paper and pencil and my mind XD

girlgoyleh. · Answer

could you show me?

yolomcswagginsggg · Answer

sure

tyteen4a03 · Answer

@yolomcswagginsggg You are supposed to show the steps used to obtain the answer, not the answer itself.

Remember, -4 = $\frac{-4}{1}$.

yolomcswagginsggg · Answer

−425=−4251=(−42)(15)=(−21)(15)=(−2)(1)(1)(5)=−-2/5

johnweldon1993 · Answer

What I like to do, instead of dealing with dividing fractions...theres a trick where you can flip the fraction...and change it to multiplication

Ex:

$$\large a \div \frac{b}{c} = a \times \frac{c}{b}$$

So here

$$\large -4 \div \frac{2}{5} = -4 \times \frac{5}{2}$$

Which indeed = -10

Great job!

girlgoyleh. · Answer

Thank you! I knew i got it right

johnweldon1993 · Answer

A good way to check though,

You know 2/5 = 0.4

So what is -4 divided by 0.4? Also -10

tyteen4a03 · Answer

@johnweldon1993 That's not taught at schools?

girlgoyleh. · Answer

Yes it is, i just learned it