can someone helpme to find this answer; 3/4-1/2+2/5= ???? I can't figure the answer out !!!?

Answer 1

You can subtract them by making like denominaters:

3/4-1/2+2/5

The denominaters all go into 20
(whatever you do to the bottom you have to do to the top!)
3x5=15 4x5=20

15/20-1/2+2/5

1x10=10 2x10=20

15/20-10/20+2/5

2x4=8 5x4=20

15/20-10/20+8/20

You only add the numeraters

15/20-10/20=5/20

5/20+8/20=13/20


Or do it by decimals.

To change a fraction into a decimal, you divide the numerater by the denominater. *=divide

3*4=.75
1*2=.5
2*5=.4

.75-.5=.25
.25+.4=.65

To change .65 back to a fraction, you move the decimal over two places, 65, so now you put it over a hundred, because you moved it past the hundreth's place. 65/100. Now simplify. Divide both by 5, (becaus eit goes in there evenly.) Now you have 13/20. (When you move the decimal place and you have
.345, you get 34.5. You can't move it three. It's the rules!)

Answer 2

The first thing you need to do is find the common denominator. There is a number that ALL those denominators will go into....

2 and 4 will NOT go into 5, so you know 5 is NOT your common denominator.
2 and 5 will both go into *10*, but 4 will not, so you know TEN is not your common denominator.
What number will all your denominators factor into?

The common denominator is 20. How do we get it?
4x5=20
2x10=20
5x4=20

So you should have something that looks like this so far:
3/4-1/2+2/5=___ -----> __/20 - __/20 + __/20 = ___

Next, you need to multiply each numerator by the same number you used to change the denominator:

3/4 = __/20 Here, 5 was used to equal 20. Multiply the numerator by 5:
3x5=__ -----> 3/4 = 15/20

1/2 = __/20 Here, 10 was used to equal 20. Multiply the numerator by 10:
1/2 =__ -----> 1/2 = 10/20

2/5 = __/20 Here, 4 was used to equal 20. Multiply the numerator by 4.
2/5 = __ -----> 2/5 = 8/20

So far, your equation should look like this:

3/4-1/2+2/5= 15/20-10/20+8/20= ___

Now, you automatically put your denominator on the end: __/20, then you simply work the numerators straight across:
15-10+8 = __
15-10 = 5, +8 = 13.

The answer to your equation is 13/20.
Can you make it any smaller?
20 will break down, but 13 will not, so that's the answer to your problem: 13/20

Answer 3

If you had 75 cents (3/4 of a dollar), spent 50 cents (1/2 a dollar) on some gum, and then your friend gave you 40 cents (40/100 of a dollar, which is the same as 2/5 of a dollar), how much money would you have? It's probably easy to come up with the answer of 65 cents. Well, 65 cents is

$ 0.65 =$ 65/100 (just like you write on a check)

Since both 65 and 100 have 5 for a factor, then the answer is

65/100 = (13*5)/(20*5) = 13/20

Answer 4

Get a common denominator for fractions that are different.
In this case 4, 2, and 5 have 20 as a common denominator.

Convert:

3/4 - 1/2 + 2/5 to 15/20 -10/20 + 8/20

15-10+8 = 13/20

Answer 5

1 13/20

Answer 6

3/4 = 3/4
-1/2 = 2/4

=1/4

1/4 = 5/20
+2/5 = 8/20

final answer = 13/20

Answer 7

Lowest common denominator = 20

15/20 - 10/20 + 8/20 = 13/20

Answer 8

13/20

Answer 9

3/4-1/2=1/4+2/5=3/9 or 1/3

Answer 10

Divide the numerator (top number) of each fraction by its denominator (bottom number) to change the fractions into decimals, .75 -.50+.40=.65. If you want to change the answer to a fraction, .65 changed to a fraction is 65/100. This fraction must be reduced to lowest terms. Divide the numerator and denominator by the largest number that will go into both of them an even number of times. That number is 5. The fraction will be 13/20. 13 divided by 20=.65. i3/20 and .65 are both correct.