The given fractions are $\frac{1}{20}$, $\frac{2}{30}$, $\frac{1}{35}$, $\frac{1}{25}$.

The denominator of the given fractions are 20, 30, 35, 25. All the denominators are different.

Hence, they are unlike fractions.

If we break a chocolate bar into 10 pieces and take 8 out of them, it will be more than if we break the same chocolate bar into 20 pieces and take 8 out of 20. This is true for the other fractions also.

Hence $\frac{8}{10}$ is the greatest fraction among $\frac{8}{10},\frac{8}{30},\frac{8}{40},\frac{8}{20}$.

We can also see that the numerator in all of the fractions is the same which is 8. However the numerator is increasing, 10, 20, 30, 40.

If the numerator of the fractions are same then the value of the fraction decreases if the value of the denominator increases.

The given figure is divided into 9 equal parts of small triangles out of which 5 are unshaded.

Hence, the fraction representing the unshaded portion is $\frac{5}{9}$.

The total number of objects in the bubble are 15.

Number of red stars in the bubble are 4.

Number of red marbles in the bubble are 4.

The number of red objects (stars + marbles) = 4 + 4 = 8

The fraction of red objects in the bubble is $\frac{8}{15}$.

Fractions which have the same denominator are called Like fractions.

Fractions that do not have the same denominator are called Unlike fractions.

R and S are like fractions with denominator 21.

P,Q and T are like fractions with denominator 12.

S and T are unlike fractions with different denominators.

The given fractions are like fractions because they have the same denominator.

When we add like fractions the denominator remains the same while we add the numerator.

$\frac{2}{13}+\frac{2}{13}=\frac{4}{13}$

The total number of alphabets in TELEPHONE is 9.

There are 4 vowels in TELEPHONE(E,E,E,O).

Hence the fraction of the letters that are vowel is $\frac{4}{9}$.

$\frac{1}{4}$ is also known as a quarter.

The given fractions are like fractions because all of them have the same denominator, which is 9.

To arrange the following fractions in ascending order we need to arrange their numerators in ascending order. 

1 < 3 < 4 < 7

$\therefore \frac{1}{9}<\frac{3}{9}<\frac{4}{9}<\frac{7}{9}$.