Question

John's height increased by 12.5%. This increase in height was 20cm. Calculate both John's original height and his new height.

A) Original Height: 140cm, New Height: 160cm

B) Original Height: 150cm, New Height: 170cm

C) Original Height: 120cm, New Height: 140cm

D) Original Height: 160cm, New Height: 180cm

Answer 1

D) Original Height = 160 cm, New Height = 180 cm

Step-by-step explanation:

You can find the answer by using the equation that would calculate the height increase. Below it shows the process of rearranging and calculating the original and new heights.

Original * 12.5% = 20 cm

20/0.125 = Original

Original = 160

160 + 20 = New

New = 180

Answer 2

John's original height was 160 cm and his new height is 180 cm after a 12.5% increase, which equates to a 20 cm growth, making the correct answer D).

Step-by-step explanation:

The question involves a basic percentage increase problem in mathematics, which requires calculating John's original and new height after a 12.5% increase. To find the original height, we need to recognize that a 12.5% increase that corresponds to 20 cm means that 12.5% of the original height is equal to 20 cm. Therefore, to find the original height, we divide the increase by the percentage increase expressed as a decimal:

• Original Height = Increase / Percentage Increase
• Original Height = 20 cm / 0.125
• Original Height = 160 cm

Once we have the original height, we can calculate the new height by adding the increase:

• New Height = Original Height + Increase
• New Height = 160 cm + 20 cm
• New Height = 180 cm

Therefore, John's original height was 160 cm and his new height is 180 cm, making the correct answer D).