Which of the following numbers could be added to 3/14 to make a sum greater than 1/2?

one-fourth

one-third

two-sevenths

three-fourteenths

To determine which of the numbers could be added to 3/14 to make a sum greater than 1/2, we can convert 1/2 to an equivalent fraction with a denominator of 14 for easier comparison. To do this, we multiply both the numerator and the denominator by 7 (since 14 is 7 times 2):

1/2 = (1 * 7) / (2 * 7) = 7/14

Now we need to check which of the given numbers, when added to 3/14, results in a sum greater than 7/14.

Let's look at each option:

One-fourth (1/4):
To add 1/4 to 3/14, we first need to find a common denominator. The least common multiple (LCM) of 4 and 14 is 28. So we convert each fraction:

1/4 = (1 * 7) / (4 * 7) = 7/28
3/14 = (3 * 2) / (14 * 2) = 6/28

Adding them together gives us:

7/28 + 6/28 = 13/28

We need to compare this sum to 1/2 in the common denominator of 28:

1/2 = (1 * 14) / (2 * 14) = 14/28

Since 13/28 < 14/28, one-fourth is not enough to make the sum greater than 1/2.

One-third (1/3):
Now let's find a common denominator for 1/3 and 3/14. The LCM of 3 and 14 is 42.

1/3 = (1 * 14) / (3 * 14) = 14/42
3/14 = (3 * 3) / (14 * 3) = 9/42

Adding them together gives us:

14/42 + 9/42 = 23/42

Comparing this to 1/2 with a common denominator of 42:

1/2 = (1 * 21) / (2 * 21) = 21/42

Since 23/42 > 21/42, one-third is enough to make the sum greater than 1/2.

Two-sevenths (2/7):
To add 2/7 to 3/14, we can find a common denominator, which is 14 in this case.

2/7 = (2 * 2) / (7 * 2) = 4/14
3/14 = (3 * 1) / (14 * 1) = 3/14

Adding them gives us:

4/14 + 3/14 = 7/14

We already know that 7/14 is equivalent to 1/2, so two-sevenths added to 3/14 will exactly make 1/2, but it will not be greater than 1/2.

Three-fourteenths (3/14):
If we add another three-fourteenths to 3/14:

3/14 + 3/14 = 6/14

Converting 6/14 to have the same denominator as 1/2 with a denominator of 14:

6/14 is equivalent to 3/7, and we know that this is less than 7/14 or 1/2.

Therefore, the only fraction among the options provided that, when added to 3/14, makes a sum greater than 1/2, is one-third (1/3).