Read the number 31556926 out aloud. Was it easy to do? It may have been quite difficult. You had to decide, 'Is the number bigger than a million or not?', 'Does it begin with 3 million, 31 million or 315 million?'.
It is necessary to write large numbers in a helpful way. It is usual to group the digits of large numbers in threes from the decimal point.
A small gap is left between each group.
31556926 should be written as 31 556926.
Now it is easy to see that the number begins with 31 million. In words we would say or write this number as thirty one million, five hundred and fifty-six thousand, nine hundred and twenty-six.
Write the number 8702614235 correctly, then express it in words.
Grouping the number in sets of three digits from the right-hand side:
eight billion, seven hundred and two million, six hundred and fourteen thousand, two hundred and thirty-five.
Note: We no longer use commas between the groups of digits. Many countries use a comma as a decimal point; thus, to avoid confusion do not use commas for grouping the digits.
Write the following numbers, grouping digits in threes from the decimal point. (Use spaces, not commas.) Then, working in pairs and taking turns, say each number aloud to your partner.
1) 1 million
5) 8 trillion
Digits and Words
What do the numbers in the following headlines stand for?
FOOD IMPORTS RISE TO Nl BILLION
OIL PRODUCTION NOW 2·3 MILLION BARRELS DAILY
FLOODS IN INDIA - 0·6 MILLION HOMELESS
NEW ROAD TO COST N2 1/4 TRILLION
N 1 billion is short for N 1000000000
2·3 million = 2·3 x 1000000 = 2300000
0·6 million = 0·6 x 1000000 = 600000
N2 1/4 trillion = N2·25 trillion
= N2 250 000 000 000
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