Arithmetic of Computers

Your answer :

2 − ( − 3) = 5 − 16 + 2 = − 14 1 + ( − 3) = − 2 − 11 + ( − 1) = − 12 ⎫⎬⎭This group contains a mistake.

Well, let’s see:

	RULE

2 − ( − 3)	To subtract any number, change the sign of the number being subtracted; then add instead, following the rule, in this case, for addition of like signs.
= sign changed ↓ 2 + ( + 3) = 5 ↑ add instead

1 + ( − 3) = − 2	To add numbers of unlike sign, find the difference of the absolute values, attach the sign of the number with the larger absolute value.

− 16 + 2	Use rule for adding numbers of unlike sign, as given above.
= ( − 16) + ( + 2) = − 14

− 11 + ( − 1) = − 12	To add numbers of like sign, add the absolute values and attach the common sign.

These are all correct. Return to Page 93 and try again.