Question

There are 51 students in three classes. How many students are there in 5 such
classes?​

Answer 1

Answer:

85

Step-by-step explanation:

3 classes = 51 students

1 class = 51/3 = 17

Students in 5 classes = 17*5 = 85

Answer 2

Answer:

There are 85 students in 5 classes

Step-by-step explanation:

Let's say that there are equal number of students in each class.

Now, there are two unique methods to solve it.

Method 1 (Unitary method)

3 classes have 51 students

When the number of students in each class are equal.

3 classes = 51 students

1 class = 51/3 students

1 class = 17 students

Thus, in 5 classes,

1 class = 17 students

5 classes = 17 × 5 students

5 classes = 85 students

Hence, there are 85 students in 5 classes.

Method 2 (Proportionality method)

3 classes have 51 students

Let 5 classes have x students

Since, there are equal students in all classes they are proportional.

Thus,

3 : 51 :: 5 : x

We know that,

Product of extremes = Product of means

3 × x = 51 × 5

3x = 255

x = 255/3

x = 85 students

OR

(3/51) = (5/x)

Cross multiplying we get,

3 × x = = 51 × 5

3x = 255

x = 255/3

x = 85 students

Hence, there are 85 students in 5 classes.

Hope it helped and believing you understood it........All the best