Question

In a survey of 90 students 20 choose rock.40 chose hip hop 30 chose country. In a school of 360 students how many would be expected to chose hip hop or rock

Answer 1

Answer:

The students would be expected to choose rock be 80 or students choose hip hop be 160 or choose to country be 120.

Step-by-step explanation:

Given:

In a survey of 90 students 20 choose rock, 40 choose hip hop and 30 choose country.

Now, to find the students expected to choose hip hop or rock or country in a school of 360 students.

Let the number of students expected to choose rock be $x.$

Let the number of students expected to choose hip hop be $y.$

Let the number of students expected to choose country be $z.$

Total number of students = 360.

Now, to get the number of students choosing hip hop or rock or country by using cross multiplication method:

In a survey of 90 students 20 choose rock.

So, 90 is equivalent to 20.

Thus, 360 is equivalent to $x$.

$\frac{90}{20} =\frac{360}{x} \\\\By\ cross\ multiplying\ we\ get:\\\\90x=7200\\\\Dividing\ both\ sides\ by\ 90\ we\ get:\\\\x=80.$

Thus, the number of students expected to choose rock is 80.

Now,

In a survey of 90 students 40 choose hip hop.

So, 90 is equivalent to 40.

Thus, 360 is equivalent to $y.$

$\frac{90}{40} =\frac{360}{y} \\\\By\ cross\ multiplying\ we\ get:\\\\90y=14400\\\\Dividing\ both\ sides\ by\ 90\ we\ get:\\\\y=160.$

Therefore, 160 students expected to choose hip hop.

And,

In a survey of 90 students 30 choose country.

So, 90 is equivalent to 30.

Thus, 360 is equivalent to $y.$

$\frac{90}{30} =\frac{360}{z} \\\\By\ cross\ multiplying\ we\ get:\\\\90x=10800\\\\Dividing\ both\ sides\ by\ 90\ we\ get:\\\\x=120.$

Hence, 120 students expected to choose country.

Therefore, the students would be expected to choose rock be 80 or students choose hip hop be 160 or choose to country be 120.