Body Mass Index for Class 5 Maths

Body mass index measures the body’s fat depending upon height and weight. Here students will learn about body mass index meaning, normal BMI ranges, body mass index chart, and body mass index formula. The concept also connects the students with operations on large numbers in math.

Body Mass Index Meaning:

Every individual is different when it comes to body weight.

Various factors influence the ideal weight of an individual.

A person may define an ideal weight as the one in which they find themselves comfortable.

However, improper body weight might lead to various diseases, such as:

• Obesity
• Cardiovascular disease (CVD)
• High Blood Pressure.

What is Body Mass Index?

Body Mass Index (BMI) is the ratio of a person’s weight in kg (or pounds) to the square of the person’s height in m (or feet). A low BMI indicates low body fatness, and a high BMI indicates high body fatness.

Normal BMI Ranges:

• If the BMI is less than 18.5 means, a person is underweight.
• A BMI of between 18.5 and 24.9 is ideal.
• A BMI of between 25 and 29.9 is overweight.
• A BMI over 30 indicates obesity.

Body Mass Index Chart:

Body Mass Index Formula:

The formula to calculate the BMI is as follows:

BMI =

From the formula of Body Mass Index, it follows that,

Weight (in Kg) = BMI * Height * Height (in m)

Operation on Large Numbers:

Question 1:

Arpita Found That Her Body Weight Is Equal to 81,000 G and Her Height Is Equal to 1.5 m. Calculate Her Body Mass Index.

Answer 1:

Body weight = 81,000 g
We know 1 kg = 1000 g.
Therefore, 81,000 g = 81 kg.
Height = 1.5 m
The formula to calculate the Body Mass Index is as follows:

BMI =
BMI =
    =

  =36

Therefore, Arpita’s body mass index is equal to 36.

Question 2:

Rima Was Not Well, so She Visited the Doctor. The Doctor Measures Her Body Weight Rima As 30 kg and Her Height As 3 m. Calculate Whether Her Body Was Underweighted, Ideal-Weighted, or Overweighted.

Answer 2:

Body weight = 30 kg
Height = 2 m
The formula to calculate the Body Mass Index is as follows:

BMI =
BMI =
    =

  = 7.5

The Body mass Index of Rima is equal to 7.5, less than 18.5. Therefore, she is underweight.

Question 3:

The Two Sisters, Jaya and Zoya, Have the Same BMI, 18.45. the Height of Jaya Was 2 m, and That of Zoya Was 1.2 m. Find the Body Weight of Each Sister.

Answer 3:

Step 1: Body Mass Index = 18.45.

Height of Jaya = 2 m.
The formula to calculate the Body Mass Index is, Therefore, the weight of the body is

Weight (in kg) = BMI * Height * Height (in m)

Weight of Jaya = (18.45 × 2 × 2) kg
= 73.8 kg
Therefore, the weight of Jaya is equal to 73.8 Kg.

Step 2: Height of Zoya = 1.2 m

Weight of Zoya = (18.45 × 1.2 × 1.2) kg
= 26.568 kg
Therefore, the weight of Zoya is equal to 26.568 Kg.

Question 4:

Reema and Deepa Are Best Friends. The Height of Both Friends Is Equal to 160 cm. The Weight of Reema Is Equal to 61.44 kg, and the Weight of Deepa Is Equal to 78.08 kg. Calculate Who Is Fit and Healthy.

Answer 4:

Step 1: Body weight of Reema = 61.44 kg.

Height of Reema = 160 cm.
We know that 1m = 100 cm. Therefore, 160 cm = 1.6 m
The formula to calculate the Body Mass Index is as follows:

BMI =
BMI =
    =

  = 24
Therefore, Reema’s body mass index is equal to 24.

Step 2: Body weight of Deepa = 78.08 kg

Height of Deepa = 160 cm = 1.6 m.

BMI =
    =

  = 30.5

Therefore, Deepa’s body mass index is equal to 30.5.
To fit and be healthy, the BMI of the person should be between 18.5 and 24.9.
A BMI of more than 30 indicates obesity.
Therefore, Reema was fit, and Deepa was obese.

Question 5:

Animesh’s Body Weight Is 35.55 kg, and His Height Is 1.5 m. He went to the Doctor for Regular Checkups the Doctor Suggested to Him the Least Weight He Should Increase to Stay Healthy. Calculate the Least Weight Suggested by the Doctor.

Answer 5:

Step 1: Body weight of Animesh = 35.55 kg.

Height of Animesh = 1.5 m.
The formula to calculate the Body Mass Index is as follows:

BMI =
BMI =
    =

  = 15.8

Therefore, Animesh’s body mass index is equal to 15.8.

Step 2: The least BMI of the ideal weight is equal to 18.5. Therefore, Animesh should increase his weight.

Least ideal weight = (18.5 × 1.5 × 1.5) kg
= 41.625 Kg
Therefore, Animesh’s weight should be at least 41.625 kg.

Step 3: Weight of Animesh = 35.55 kg

Required Weight = 41.625
Increase weight = (41.625 – 35.55) Kg
= 6.075 kg
Therefore, the doctor must have suggested him to increase at least 6.075 kg.