Ray's New Practical Arithmetic · Arts. 77–78 · Unit 8: Operations with Compound Numbers
43. Time between dates
Goal: Your child finds the time between two dates in years, months and days, and counts the exact days between dates.
You'll need
- The book
- A slate, small whiteboard or scrap paper
- A notebook and pencil
What's in the book
Art. 77: finding time between dates by compound subtraction, with historical dates. Art. 78: counting the exact number of days between two dates, with notes and dates. Answers are printed.
The lesson, step by step
Warm-up
Ask: How many days in May? June? How many months from March to August?
The rule of thumb
Read:
In finding the time between any two dates, consider 30 days 1 month, and 12 months 1 year.
Work:
A note, dated April 14, 1875, was paid February 12, 1877: find the time between these dates.
Write 1877 2 12 over 1875 4 14 (year, month, day) and subtract with borrowing: 1 yr. 9 mo. 28 da.
Exact days
Read:
To find the time between two dates in days.
Work:
Find the number of days from May 10 to Oct. 21.
Count: rest of May 21, June 30, July 31, August 31, September 30, October 21: total 164.
Guided practice
Together:
A note dated April 18, 1877, is due June 20, 1877: how many days does it run?
(63.)
Independent practice
Your child does the historical date problems of Art. 77 and problems 2 to 6 of Art. 78. Then: how many days old is your child?
Check and wrap-up
Answers are printed. Wrap up by finding the days from today to the next birthday or holiday.