We write "3.4 cm + 4.3 cm = 7.7 cm," but the sum could be as small as cm

the smallest value of the sum is 7.65 cm.

Step-by-step explanation:

Given;

3.4 cm + 4.3 cm = 7.7 cm

To obtain the least value of the given result, we will apply the rounding-off method;

In the rounding-off method, digits between 0 to 4 will be rounded down to zero while digits between 5 and 9 will be rounded up to 1.

The smallest value of 7.7 cm = 7.65 cm (5 will be rounded up to 1 making 7.65 cm approximately 7.7 cm)

Also, other possible values of 7.7 cm include;

7.66 cm, 7.67 cm, 7.68 cm, 7.69 cm

Note :7.64 cm cannot be rounded up to 7.7 cm because 4 will be rounded down to zero making 7.64 cm approximately 7.6 cm.

Therefore, the smallest value of the sum is 7.65 cm.