Mathematics Magazine for Grades 1-12  

1/2004

You can tell more about a person by what he says about others than you can by what others say about him.
 - Leo Aikman

Grade 4

Theory: 

 Decimals

  • Decimals are a method of writing fractional numbers without writing a fraction having a numerator and denominator.

  • The fraction 37/100 could be written as the decimal 0.37. The period or decimal point indicates that this is a decimal.

  • The decimal 0.37 could be pronounced as THIRTY-SEVEN HUNDREDTHS or as ZERO POINT THREE SEVEN or ZERO POINT THIRTY-SEVEN.

  • A decimal may be greater than 1. The decimal 12.37 could be pronounced as TWELVE AND THIRTY-SEVEN HUNDREDTHS or as TWELVE POINT THIRTY-SEVEN.

Solutions from the Previous Issue:

Calculate:

  1. 33 [1+ 34 (3 × 5 + 4 2)] =

Solution: 33: [1+ 34 (3 × 5 + 4 2)] = 33 [1+ 34 (15 + 2)] = 33 [1+ 34 (17)] = 33 (1+ 2) = 33 3 = 11

  1. [10 + 2× (3  3 + 9  3)] 9 =

Solution: [10 + 2× (3  3 + 9  3)] 9 = [10 + 2× (1 + 3)] 9 = (10 + 2× 4) 9 =  (10 + 8) 9 = 18 9 = 2

  1. [10 + 2 × (3  3 + 9 3)] 9 + 2 = 

Solution: [10 + 2 × (3  3 + 9 3)] 9 + 2 =  [10 + 2 × (1 + 3)] 9 + 2 = (10 + 2 × 4) 9 + 2 =  (10 + 8) 9 + 2 =  18 9 + 2 =  2   b+ 2 = 4

  1. [(2 × 3 + 45  15)  9 + 1] 2=

Solution: [(2 × 3 + 45  15)  9 + 1] 2= [(6 + 3)  9 + 1] 2= (9 9 + 1) 2 = (1 + 1) 2 = 1

Proposed Exercises: 

  1. The owner of a motel with 100 rooms wants the room doors numbered in order from 1-100. She asks you to buy numbers and hang them on the doors. Now you must go to the store and buy all the digits you need to make the numbers. How many digits does he needs?
  2. Abraham, Wesley, Chirah, Jack, Kareem, Natalie, Shannon, and Becky were lucky enough to get tickets to the baseball playoff game. They could not get eight tickets together, so they sat in pairs in different sections of the ballpark. This gave each pair a different view of the game. Two sat behind home plate, two in the outfield stands, and two each near first base and third base.
  3. Chirah and Shannon were glad their friends caught the home run ball that flew past the outfield. Wesley and Natalie got the first baseman's autograph as he walked by them. Abraham and Jack got the closest view of the batters and of the umpire calling strikes and balls. Where did each pair of baseball fans sit?