Rounding 3

Knowing when to round

You can round:

  • If someone asks your to round.
  • If someone asks for an estimate.

If you can identify an amount of rounding that will preserve the valuable information.

Various times, people will ask you to round, they may not care about exact values.   Sometimes, you will not feel that accuracy is important in a conversation.   Sometimes, people will not appreciate your rounding numbers.   You must know when it is ok to round. You round if:

  • If someone asks you to round, do it ... it simplifies your life.
  • If inaccuracy does not hurt the conversation, round/estimate.
  • If inaccuracy hurts the conversation, don't round.  
  • Rounding HURTS a conversation.    Rounding hurts if your rounding makes the information inadequate to make a decision or make understanding impossible.   The following are examples where rounding hurts ...
    1. You owe someone $10.50.   The person says to you, "You owe me $11.00."
    2. You are buying some $32.75 tennis shoes.  The salesperson tells you the shoes cost "$40.00."
    3. You are going to Disneyland by bus.   The bus is leaving at 3:30.   You are told to be at the bus, to load, at 4:00.

The following are examples where rounding is ok:

  1. You owe Jan $10.50.   A friend asks how much you owe Jan.  You might say, "I owe about $11.00."
  2. You buy some tennis shoes for $32.75.    You tell a friend, "I bought these shoes for about $33.00."
  3. You would like to go to Disneyland.   You would like to know about what time the bus leaves.   You can go if the bus leaves in the afternoon, but, you will not be able to be at the bus in the morning.   Your friend says, "The bus leaves about 4:00."   (After knowing about what time  it leaves, and deciding you can go, you would ask for the exact time the bus leaves.)

Check Your Understanding

Which of the situations would be alright to round/estimating:

  1. I owe you $6.52.  You say to me, "You owe me $7.00."
  2. You go to the store.   You expect to spend about 2 hours.
  3. You buy something on the internet.  They say they will deliver in about 10 days.
  4. Ted owes you $64.00.   He gives you $60.00.
  5. You are 15 years and 11 months old.   You tell someone you are about 16 years old.