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1.4 number 16.
This problem is an order of operations involving decimals
and fractions, and you have a couple choices here.
Either convert to decimals or convert all to fractions.
Let's start off by converting to decimals first, and then
I'll do it the other way by converting to fractions.
Converting to decimals.
Negative 3 over 5.
We can multiply times 2 times 2 and get minus 6/10,
which is minus 0.6.
Plus 0.8 take away minus 2/5.
Again, try and make 10, 100, or 1,000 on the denominator.
Or plug it in to your calculator, 2 divided by 5.
That going to give us minus 0.4 plus 0.4.
The only thing to watch out for if you're converting to
decimals is you can only use this method and if you convert
to a decimal that ends.
So if you have a decimal that has a repeating part, like 2/3
would be 0.6666 repeating forever, then you can't use
this approach.
Now, we can go ahead.
And minus 0.6 plus 0.8 would give us 0.2.
Because we have different signs, so we keep the sign of
the bigger number to find the difference of the numbers.
And then minus negative 0.4 plus 0.4 goes to 0.
So our answer would be 0.2.
And as a fraction, 0.2 is the same as 2/10, and
2/10 reduces to 1/5.
That's doing it converting to decimals.
Convert to fractions instead.
And converting to fractions is, in a way, safer, because
you can always do it this way.
You don't have to watch out for anything.
Just some people don't like converting to fractions,
that's all.
So we have minus 3/5 plus 0.8 is the same as 8/10, take away
minus 2/5 plus 0.4.
0.4 is 4/10.
And let's go ahead and reduce.
8/10 and 4/10, we can reduce both of those.
So a rewrite, we get minus 3/5 plus divided by 2 top and
bottom, we get 4/5.
Take away minus 2/5 plus 4/10 divided by 2 top
and bottom is 2/5.
And just like with the decimals, minus 2/5
plus 2/5 goes to 0.
Minus 3/5 plus 4/5 5 is minus 3 plus 4 over five.
Different signs, therefore keep the sign of the bigger
one, positive.
And find the difference of the numbers, 1/5.
So you're going to get the same answer both ways.
Just depends on how you like doing it.