7-7 Mixture Problems

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7-7 Mixture Problems

• Objective To solve mixture problems

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• A 2 Liter solution that is 50 grape juice is
  added to a 4 Liter solution that is 25 grape
  juice.
• How many Liters will be in the resulting mixture?
• What is the of grape juice in the resulting
  mixture?

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• How many Liters of water should be added to 5
  Liters that is 40 grape juice to make a
  resulting mixture that is 10 grape juice?
• How many Liters will be in the resulting mixture?
• What is the of grape juice in the resulting
  mixture?

?????
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Example 1 If 800 mL of juice drink is 15 grape
juice, how much grape juice should be added to
make a drink that is 20 grape juice?
Step 1 The problem asks
Step 2 Let x
15 (800 mL) 100 (x mL) 20
(800mL x mL)
.15 (800) 1.00(x)
.20 (800 x)
Step 3
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Example 2 How many L of water must be added to
20 L of 24 acid solution to make a solution that
is 8 acid?
Step 1 The problem asks ______________________
Step 2 Let x
24 (20 L)
8 (_____L)
____ ( x L)
____ x .24 ( 20)
.08( )
Step 3
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Homework Page 323 4 A chemist mixes 12 L of a
solution that is 45 acid with 8 L of a solution
that is 70 acid. What is the percent of acid of
the mixture?
Step 1 The problem asks
Step 2 Let x
45 (12 L) 70 (8 L) ____ (12 L
8 L)
Step 3
.45 (12) .70 (8) _____
( 20)
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Homework Page 324 9 How many L of water must
be added to 50 L of a 30 acid solution in order
to produce a 20 acid solution?
Step 1 The problem asks
Step 2 Let x
Water
Acid
Mixture

L
Step 3
OR
____(x) .30 (50) .20(50 x)
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Homework Page 324 10 How many mL of water must
be added to 60mL of a 15 iodine solution in
order to dilute it to a 10 iodine solution?
Step 1 The problem asks
Step 2 Let x
Iodine
Dilution
Water

mL
Step 3
OR
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A chemist has 49 mL of a solution that is 50
acid. How much water should he add to make a
diluted solution that is 10 acid?Step 1 The
problem asks Step 2 Let xamount of water added
acid
water
diluted mixture





Step 3
OR
10
Homework Page 323 5 A grocer mixes 5 lb of egg
noodles costing .80/lb with 2 lbs. of spinach
noodles costing 1.50/lb. What will the cost
per pound of the mixture be?
Step 1 The problem asks
Step 2 Let x
Egg noodle
Spinach n.
Mixture

lbs
Step 3
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If I mix cashews selling at 8.00 with pecans
selling at 7.00 how many kilograms of each do I
need to get a 8 kg mix worth 7.25?Step 1 The
problem asksStep 2 Let x of kg of cashews
so of kg of pecans
cashews
pecans
mix


8.00 7.00 7.25
x 8
8x 7( ) 7.25(8)


Step 3
12
A health food store sells a mixture of raisins
and roasted nuts. Raisins sell for 3.50/kg and
nuts sell for 4.75/kg How many kilograms of
each should be mixed to make 20 kg of this snack
worth 4.00/kg?
Step 1 The problem asks
Step 2 Let x
Raisins Nuts Mixture


Step 3
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Mrs. Colbert has 55 coins in her purse. She has
dimes and quarters which total 10.00. How many
dimes does she have?
Step 1 The problem asks
Step 2 Let x
Dimes Quarters Total


Step 3