The length of a pencil is measured with two rulers. report the length of the pencil from each ruler with the proper number of digits.

Answer

Length measured using Ruler A= 1.17 dm

Length measured using Ruler B=1.18 dm

Step by Step Explanation:

I have added the missing photograph which shows the length of pencil being measured with two rulers.

Ruler A has marking separated by 1 dm

Ruler B has marking separated by 0.1 dm

Length measured using Ruler A= 1.17 dm

(As we can see I have added the middle markers, we can see the tip of pencil is somewhere between 1 and 1.25, it is more than 1.125 but lesser than 1.25, it is somewhere around 1.2 and 1.125 dm, approximately equal to one half of 1.25 which is 1.125 with addition of one of the three halves of half of 1.125 which is 1.125+0.045 dm hence 1.17dm)

Length measured using Ruler B=1.18 dm

(we can see the tip of pencil is just before 1.2 dm, it is clear that the value is precisely 1.18 and not 1.19 dm)

Tip:Always measure one more decimal than given by the ruler when unsure about the exact value

-2

7 - 9 = -2

reversed:

-2 + 9 = 7