Arithmetic Solutions

  1. One method to subtract mixed numbers is to change them to improper fractions.   Borrowing is not necessary using this method:
     
     
  2. What is of 78 ?
    In mathematics, 'of ' means to multiply:

     
  3. Find:   7 - 2.042
    Rewrite the 7 as 7.000 then place the numbers in a column, lining up decimal points, and subtract:

     
  4.   is approximately equal to ?
    M    ove the decimal point to the right two places in the numerator and denominator.  This is a shortcut for multiplying the original fraction by 100/100:

    Then round 9100 down to 9000 and round 28 up to 30:
     
    Divide:

    = 300
     
  5. What percent of 420 is 63 ?
    There are many different methods used to do this problem.  One way to view it is:
    a part (63) divided by the total (420). 
    Use long division to obtain:

    Then multiply by 100%:  15%
     
  6. In a fruit bowl, there are four apples, three oranges, seven peaches, and five bananas.  What is the ratio of peaches to fruit?
    The r    atio of 7 peaches to 19 pieces of fruit is:  7 to 19 or 7 divided by 19 or 
     
  7. 17% is equal to all of the following except ?
    17 percent means 17 per one hundred.
    1.     equals 17 per one hundred
    2.   17  does not equal 17 per one hundred
    3.   0.1 + 0.07 = 0.17 which equals 17 per one hundred
    4.   0.2 - 0.03 = 0.17 which equals 17 per one hundred

    Final answer:  17
     

  8. Bob's annual salary was $24,000 last year.  This year he received a 4% raise.  What is his annual salary this year?
    Multiply 4% by 24000:   0.04(24000) = 960
    Add 960 to last year's salary to obtain:  $24,960
     
  9. Find:   -3 + 4(-2)
    Order of operations:  parentheses; exponents; multiplication or division left to right; addition or subtraction left to right.
    Following order of operations:
       -3 + 4(-2)
    = -3 + (-8)
    = -11 
     
  10. Find:  -2 + 5 - 3(1 - 2)²
    Following order of operations:
       -2 + 5 - 3(1 - 2)²
    = -2 + 5 - 3(-1)²
    = -2 + 5 - 3(1)
    = -2 + 5 - 3
    = 3 - 3
    = 0

On to the next review:  Elementary Algebra