I assume that the numbers are supposed to be written as 7.14 x 10^10 for December and 3.21 x 10^10. The total mail delivered is the sum of these two numbers.
(7.14 x 10^10) + (3.21 x 10^10) = 1.035 x 10^11
You would earn 60 for 6 hours of work.
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Answer:
Let's solve your equation step-by-step.
3 / 4 y = 9
Step 1: Multiply both sides by 4/3.
(4 / 3 ) * ( 3 / 4 y ) = ( 4 / 3 ) * ( 9 )
y = 12
Answer:
y = 12
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Insert 12 to the y value:
3 / 4 ( 12 ) = 9
9 = 9
True
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The answer is 6.
Division is the opposite of multiplication and 3x6 is 18
add the two equations together
5a+5b=25
-5a+5b=35
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0 + 10b =60
divide by 10
b=6
5a + 5b = 25
5a +5(6) = 25
5a +30 =25
subtract 30 from each side
5a =-5
divide by 5
a = -1
Answer (-1,6)
or a=-1 b=6