Help with simple math problem.7/16+7/20+1/5?

Question

/ means fraction
Can not find LCD

Answer 1

35 / 80 + 28 / 80 + 16 / 80
79 / 80

Answer 2

The question was asked:
I need help with a simple math problem: 7/16+7/20+1/5?

There is a proper answer and a quick and dirty answer.

The proper answer is to find the least common denominator (LCD) and multiply all the fractions by all the components except those of the one you are upgrading at the moment.

The quick and dirty answer is to create what we shall call the greatest common denominator (GCD). This will make all the denominators the same and the numerator proportionally as large for each fraction.

1) Multiply each fraction by all the other denominators.
2) Now you can add all the numerators together and reduce the result as far as possible.

Example:
1/2 + 1/3 + 1/6

1/2*(3*6) + 1/3*(2*6) + 1/6*(2*3)

1/2*(18) + 1/3*(12) + 1/6*(6)

18/36 + 12/36 + 6/36

18 + 12 + 6 / 36

36/36

1

Our problem: 7/16+7/20+1/5
16*20*5=1600 for the bottom part

7*(20*5) + 7*(16*5) + 1*(16*20)
700 + 560 + 320
1580/1600
790/800 (reduced by 2)
395/400 (reduced by 2)
79/80 (reduced by 5)

If I could have seen it, I could have reduced by 4 or even 20 and saved myself a step during the reduction.

The LCD is 80 but there is a lot more figuring that way. The GCD has the least amount of figuring.

Answer 3

This is a tough one, but sometimes the least common denominator is a multiple of the denominators. Here, if you multiply 16 x 5, you get 80. 80 is the LCD of 16, 20, and 5.

Then to solve, you multiply each fraction to get 80 as denominator:

7/16 = 35/80 (b/c 16x5=80)
7/20 = 28/80 (b/c 20x4=80)
1/5 = 16/80 (b/c 5x16=80)

So, you have
35/80 + 28/80 + 16/80 = Then add the numerators:

= 79/80

Answer 4

LCD tabulation:
16, 20, 5 = 4
4, 5, 5 = 5
4

LCD = 4 * 5 * 4 or 80

Computation:
= 7/16 + 7/20 + 1/5
= 35/80 + 28/80 + 16/80
= 79/80

Answer: 79/80

Answer 5

1/5 = 4/20, so we have 7/16 + 7/20 + 4/20 = 7/16 + 11/20
And the smallest common denominator of 16 and 20 = 80, because 16 and 20 have the same divisor 4, so the LCD is 16x20/4=80
So we have 35/80 + 44/80 = 79/80 !

Answer 6

(7/16)+(7/20)+(1/5)

now find the factors of each:

16 = 2*2*2*2
20 = 5*2*2
5 = 5*1

Now make sure each factor is represented:
LCD = 5*2*2*2*2*1 = 80
(Notice how 5*1 is represented for 5; 5*2*2 is represented for 20; and 2*2*2*2 is represented for 16. Also notice that you do NOT need to put two 5's - only one is needed to represent)

Now rewrite your fractions:

(35/80)+(28/80)+(16/80)

Now add the numerators: 35+28+16 = 79

ANS: (79/80)

Answer 7

The least common denominator among the 3 fractions is 80. As a result:

35/80 + 28/80 + 16/80 = 79/80.

Answer 8

the LCD is 80

Answer 9

that is not any longer shows approximately undesirable well-being in any respect! you purely have been given slightly rusty in calculating this. So, the 1st calculation is incorrect, as a results of fact a million-(a million-5) isn't equivalent to a million-a million-5. you are able to no longer upload the brackets to it. think of approximately it that way- in a million-a million-5, we take the huge style a million. Then, we get rid of a million from it, and then, we get rid of five from the end result. So, because we get rid of the two a million and 5, we are able to assert, that we purely ought to calculate a million-(a million+5). You get rid of the two a million and 5 at the same time. So, that is a million-6: -5. that is that straightforward.