Page 239 - New Medley 5 Semester 1

(b) 3 months = 3 × 30 days = 90 days

( 1 month = 30 days)

(c) 2 years = 2 × 365 days = 730 days

( 1 year = 365 days)

(d) 345600 seconds = 345600 ÷ 60 minutes = 5760 minutes

= 5760 ÷ 60 hours = 96 hours

= 96 ÷ 24 days = 4 days

Example 3: Convert 5000 days into years, months, weeks and days.

Solution: We have 5000 days = 5000 ÷ 365 years

= 13 years + 255 days

Again, 255 days = 255 ÷ 30 months

= 8 months + 15 days

= 8 months + 14 days + 1 day

= 8 months 2 weeks 1 day

Thus, 5000 days = 13 years 8 months 2 weeks 1 day.

Some Other Units

1 decade = 10 years (e.g., 1991 – 2000, 2001 – 2010, etc.)

1 century = 100 years (e.g., 1801 – 1900, 1901 – 2000, etc.)

1 millennium = 1000 years (e.g., 1001 – 2000, 2001 – 3000, etc.)

Sometimes, you see ad or bc is written with a Calendar Era. ad is the

short form of the Latin word ‘Anno Domini’ which means ‘in the year of
the Lord’ and bc is the short form of ‘Before Christ’. ad 2015 means 2014

years have passed after Christ’s birth.

bc and ad are used to indicate the date of any historical events, e.g., one

of the greatest mathematician-astronomer Aryabhatta was born in ad 476

and died in ad 550. He wrote his famous treatise the “Aryabhatia” and
discussed about ZERO (0) for the first time.

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