Question

55% of the students in class v are girls. If the strength of the class is 40 , find the number of girls and boys in the class. *​

Answer 1

Given

Percentage of girls in Class 5 ⇒ 55%

Total number of students in Class 5 ⇒ 40

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To Find

The number of boys and girls in the class.

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Solution

To find the total number of boys and girls separately we must find the number of girls and subtract it from the total strength.

No. of Girls ⇒ 55% of 40

⇒ $\dfrac{55}{100} \times 40$

⇒ $\dfrac{2200}{100}$

⇒ 22

∴ There are 22 girls in the class.

Now we will subtract 22 from 40 to obtain the number of boys in the class.

⇒ 40 - 22

⇒ 18

∴ There are 18 boys in the class.

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Answer 2

♣ Qᴜᴇꜱᴛɪᴏɴ :

• 55% of the students in class V are girls. If the strength of the class is 40 , find the number of girls and boys in the class.

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♣ ɢɪᴠᴇɴ :

• 55% of the students in class V are girls
• Strength of the class is 40

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♣ ᴛᴏ ꜰɪɴᴅ :

• Number of girls and boys in the class

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♣ ᴀɴꜱᴡᴇʀ :

$\bigstar\:\:\bf{Number\:\:of\:\:girls=22}$

$\bigstar\:\:\bf{Number\:\:of\:\:boys=18}$

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♣ ᴄᴀʟᴄᴜʟᴀᴛɪᴏɴꜱ :

55% of the students in class V are girls

Let number of boys be x, then :

$\implies\sf{(55\%\:\:of\:\:40)+x=40}$

$\implies\sf{\dfrac{55}{100}\times 40+x=40}$

$\implies\sf{\dfrac{55}{5}\times 2+x=40}$

$\implies\sf{11\times 2+x=40}$

$\implies\sf{22+x=40\:\:\:.........(1)}$

$\bf{Number\:\:of\:\:girls=22\:\:\:........(2)}$

Putting (2) in (1) :

$\implies\sf{22+x-22=40-22}$

$\implies\sf{22+x-22=18}$

$\implies\bf{x=18}$

$\bf{Number\:\:of\:\:boys=18}$