We will learn representation of numbers on the abacus.
We can show 100 on an abacus with three vertical rods. The rods represent place value of hundreds, tens and ones. We add beads on the rods to show different number. Each rod can hold up to 9 beads.
This shows 9 ones
If we add 1 more to 9 it is 10 ones. Regroup 10 ones as 1 ten.
This shows 9 tens and 9 ones. The number is 99.
If we add 1 more to 99 it is 10 tens. Regroup 10 tens as 1 hundred.
1 bead in the hundreds place represents 1 hundred.
To read a 3-digit number first read the hundreds place and then the last two digits place.
Let us take this example:
5 beads in the hundreds place means 5 hundreds.
4 beads in the tens place means 4 tens.
2 beads in the ones place means 2 ones.
The number can be written as 542 = 5 hundreds 4 tens and 2 ones
Five hundred forty-two
Questions and Answers on Representation of Numbers on the Abacus:
1. Read the following numbers on the abacus and write the number names in the given space.
1. (i) One hundred twenty-seven.
(ii) Two hundred seven.
(iii) Three hundred twenty-nine.
2. Read the given number on the abacus and fill in the blanks. One has been done for you.
2. (ii) 3 hundreds; 8 tens; 6 ones
(iii) 4 hundreds; 5 tens; 0 ones
(iv) 6 hundreds; 5 tens; 5 ones
(v) 1 hundreds; 9 tens; 0 ones
(vi) 7 hundreds; 2 tens; 8 ones
3. Draw beads to show the following numbers on the abacus.
4. Read the numbers shown on the abacus. Write the number and the number name in the given space.
4. (i) 111; One hundred one
(ii) 388; Three hundred eighty-eight.
(iii) 406; Four hundred six
(iv) 808; Eight hundred eight
(v) 776; Seven hundred seventy-six
(vi) 642; Six hundred forty-two