Answer:
The second option: 3 (6 - 5n)/20n
Step-by-step explanation:
Make sure all fractions have a common denominator:
Step 1. Find a common multiple between all three denominators
5, 4, and 10 all have a common multiple of 20. Proof: 5 × 4 = 20, 4 × 5 = 20, and 10 × 2 = 20
Step 2. Multiply the denominators to get to 20. Whatever you do to the bottom (denominator) must be done to the top (numerator).
1/5n × 4/4 = 4/20n
3/4 × 5n/5n = 15n/20n
7/10n × 2/2 = 14/20n
Your fractions now all have a common denominator of 20n.
Rewrite the equation using the new fractions:
4/20n - 15n/20n + 14/20n
Only focus on adding/subtracting the numerators; the denominators will stay the same: 20n.
(4 - 15n + 14)/20n
Combine like terms:
(18 - 15n)/20n
Factor out any numbers possible:
3(6 - 5n)/20n
Note* 3 go into both 18 and 15, which allows us to factor 3 out. 18 ÷ 3 = 6 and 15 ÷ 3 = 5, giving us our new numbers inside the parentheses.
-2a from both sides then divide by -5 and a=1
In 1 hour you'll have 4 cells so multiply that by 3 and you will have 12 cells in 3 hours
The numbers are: 36 and 11 .
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Explanation:
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Let us represent the TWO (2) numbers with the variables;
"x" and "y" .
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x + y = 47 .
y − x = 25.
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Since: " y − x = 25 " ;
Solve for "y" in terms of "x" ;
y − x = 25 ;
Add "x" to each side of the equation:
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y − x + x = 25 + x ;
to get:
y = 25 + x .
Now, since:
x + y = 47 ;
Plug in "(25 + x)" as a substitution for "y"; to solve for "x" :
x + (25 + x) = 47 ;
x + 25 + x + 47 ;
2x + 25 = 47 ;
Subtract "25" from each side of the equation:
2x + 25 − 25 = 47 − 25 ;
2x = 22 ;
Divide EACH SIDE of the equation by "2" ;
to isolate "x" on one side of the equation; and to solve for "x" ;
2x / 2 = 22 / 2 ;
x = 11 ;
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x + y = 47<span> ;
</span>Plug in "11" for "x" into the equation ; to solve for "y" ;
11 + y = 47 ;
Subtract "11" from EACH SIDE of the equation;
to isolate "y" on one side of the equation; and to solve for "y" ;
11 + y − 11 = 47 − 11 ;
y = 36 .
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So: x = 11 , y = 36 ;
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Let us check our work:
y − x = 25 ;
36 − 11 =? 25 ? Yes!
x + y = 47 ;
36 + 11 =? 47 ? Yes!
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The numbers are: 36 and 11 .
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<span>1. </span><span>Gaetano spent 37.80 dollars
including the tax for a pair of jeans
=> the tax is 8%, how much is the original cost of a pair of jeans?
=> 8% = 8/100
=> .08
Now, multiply .08 by 37.80 to get the 8% of 37.80
=> 37.80 x .08
=> 3.024 – this is the tax of a pair of jeans.
now, let’s subtract 3.024 by 37.80 to get the actual price of a pair of jeans.
=> 37.80 – 3.024
=> 34.776 – the original price of a pair of jeans without tax.
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