What number does point C represent on the line?
First, we identify point C. We can use the rest of the information on the number line to solve for the number of point C. If you notice the two numbers after point C, you’ll see that we’re going from 770 to 776. From one dash to the next, we’ve added seven units. And that means, from point C to the number 770 is an increase of seven units.
But we want to go backwards. We want to start at 770 and move to point C, move in the left direction seven units. Moving to the left seven units is the same thing as subtracting seven. We take the number 770 and subtract seven units.
Starting in the units place, we can’t subtract seven from zero. So we borrow from our tens place. That leaves us with six tens and ten ones. From there, we can say 10 minus seven equals three. We bring down the six from our tens place and bring down the seven from our hundreds place. This tells us that point C is equal to 763.