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The length of a rectangle is 2 inches less than 3 times the number of inches in its width. If the perimeter of the rectangle is 28 inches, what is the width and length of the rectangle?

The successor of a certain number when added to twice the number produces 61. What is the number?

How many pounds of cashew nuts worth 75 cents a pound must be mixed with 10 pounds of pecans worth $1.50 a pound to make a mixture worth $1.00 a pound?

Maple syrup worth $6.00 a gallon and corn syrup worth .80 cents a gallon are used to make a mixture worth $2.36 a gallon. How many gallons of each kind of syrup are needed to make 50 gallons of the mixture?

A purse contains 21 coins consisting of nickels and dimes. Find the number of coins of each kind if the total value is $1.65.

Carol bought 36 two-cent and three-cent stamps for $1.00. How many stamps of each kind did she buy?

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  • Jim
    Lv 7
    1 decade ago
    Favorite Answer

    1. P = Perimeter

    P = 2*(SideA + SideB)

    P = 2SideA + 2SideB

    Let SideA be the length which is 2 inches LESS than 3 x SideB (the width). Therefore, substitute SideB

    into Side A:

    28 = (3(2(SideB))) - 2 + 2SideB

    28 = 6SideB - 2 + 2SideB

    28 + 2 = 8SideB

    30 = 8SideB

    30/8 = Side B

    3 6/8 = 3 3/4 = 3.75

    Prove it:

    28 =? 6(3.75) - 2 + 2(3.75)

    28 = 20.5 + 7.5

    28 = 28, CHECK!

    So SideB, which is the width is equal to 3.75 inches

    The length then, is 3.75 - 2 inches = 1.75 inches!

    ----------------------------------------------------------------------------------------------------------

    Let 0 be a number (yes, zero is a number), then

    0, 30 and 2 x 30 = 60, (two additions of 30 = 60) add 1 to it to get 61, therefore, the number is 30

    ----------------------------------------------------------------------------------------------------------

    The next two are mixture problems, see this site for help:

    http://www.drdelmath.com/special_topics/mixture_pr...

  • 4 years ago

    a million. 4n = 30-10 = 20 n = 20/4 n = 5 2. 2p = 11+13 = 24 p = 24/2 p = 12 3. 5x-25 = 10 5x = 10+25 = 35 x = 35/5 x = 7 4. x = 8+a million x = 9 5. -0.5 = fifty 5 + 4v -0.5 - fifty 5 = 4v -fifty 5.5 = 4v -fifty 5.5/4 = v v = -13.875

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