What is happening
You arrive at a tuck shop counting five-rupee coins into a bag.
The bag has to hold forty-five rupees in five-rupee coins exactly. The shopkeeper keeps losing count partway.
Counting in fivesRunning
Value in the bag
90₹
Target value
45₹
Value in the bag is over by 45 ₹
Number line. Coins at 18 coins. Value in the bag 90 ₹, Target value 45 ₹. Currently value in the bag is over by 45 ₹.
What has to balance