Sasha, Rudy, and Mario each have #1 3/4# cups of flour. Can they make a recipe for bread that needs 5 cups of flour?

2 Answers
Aug 26, 2017

Answer:

#"yes"#

Explanation:

#"calculate the total amount of flour they have"#

#rArr3xx1 3/4#

#"change "1 3/4" to an "color(blue)"improper fraction"#

#=3/1xx7/4=(7xx3)/(1xx4)=21/4=5 1/4#

#"they have the required 5 cups with "1/4" left over"#

Aug 26, 2017

Answer:

Yes there is enough flour to make the bread.

Over the top explanation given so you can see where everything comes from.

Explanation:

#color(blue)("Three very important facts")#

#color(brown)("Fact 1: ")#

A structure of a fraction consists of

#color(white)("bbbbbb.")("count")/("size indicator of what you are counting")#

#color(white)("ccccccccccc")("count")/("size indicator")->("numerator")/("denominator")#

..............................................................
#color(brown)("Fact 2: ")#

You can not #ul("directly compare")# counts (numerators) unless the size indicators (denominators) are the same.

.................................................................
#color(brown)("Fact 3: ")#

Multiply by 1 and you do not change the 'true' value of a fraction or number. However, 1 comes in many forms so you can change the way a fraction looks without changing its value.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Answering the question")#

I chose to make the size indicator such that we are counting quarters.

Converting 5 into quarters:

#color(green)(5color(red)(xx1)color(white)("cccc") ->color(white)("c"vvvv) 5color(red)(xx4/4) = 20/4)#

Converting #1 3/4# into all quarters:

#color(green)(1 3/4color(white)("cccc")->color(white)("cccc") [1color(red)(xx1)]+3/4)#

#color(green)(color(white)("ccccccc")->color(white)("cccc")[1color(red)(xx4/4)] + 3/4 = 7/4)#

So the total of all the #1 3/4# cups is #3xx7/4 = 21/4# cups

The amount needed to make the bread is #5 =20/4# cups

As 21 is more than 20 then yes, there is enough to make the bread