Question

Lily planted a sunflower and she is observing its growth. Last week the height of the sunflower was 1 m and 30 cm, and now it has grown 40 cm more. What is the current height of the sunflower in cm?

• A. 170

Answer 1

The correct option is A 170
Last week, the height of the sunflower was 1 m and 30 cm.

Here, 'and' signifies addition.

$\therefore$ Last week height $=1\text{m}+30\text{cm}$

Over the past week, the height increased by $40\text{cm}$.

$\therefore$ Current height $=1\text{m}+30\text{cm}+40\text{cm}$

To perform addition, let's make all the terms as like-terms.

We know, $1\text{m}=100\text{cm}$

$\Rightarrow 1\text{m}+30\text{cm}+40\text{cm}=100\text{cm}+30\text{cm}+40\text{cm}=(100+30+40)\text{cm}=170\text{cm}$

Hence, the current height is 170 cm.