If Robert buys a candy bar for 78 cents how much change does he get back from one-dollar bill?

To calculate the change Robert receives, we subtract the cost of the candy bar from the one-dollar bill.

Cost of candy bar: 78 cents

Amount paid: $1.00 (100 cents)

Change = Amount paid - Cost of candy bar

= 100 cents - 78 cents

= 22 cents

Therefore, Robert will receive 22 cents in change