Answer:
<u>36</u>
Step-by-step explanation:
Let <em>q</em> be the number of quarts of pure antifreeze that needs to be added to get the desired solution.
8 quarts of 40% solution contains 0.40 × 8 = 3.2 quarts of antifreeze.
The new solution would have a total volume of 8 + <em>q</em> quarts, and it would contain a total amount of 3.2 + <em>q</em> quarts of antifreeze. You want to end up with a concentration of 60% antifreeze, which means
(3.2 + <em>q</em>) / (8 + <em>q</em>) = 0.60
Solve for <em>q</em> :
3.2 + <em>q</em> = 0.60 (8 + <em>q</em>)
3.2 + <em>q</em> = 4.8 + 0.6<em>q</em>
0.4<em>q</em> = 1.6
<em>q</em> = 4
The expression is 5x - 2y
Use PEMDAS and work out the rest
x = 3 and y = 4
5 x = 5 x 3 = 15
2 y = 2 x 4 = 8
15( x ) - 8 (y) = 7
The answer is 7
Hope This Helps You!
Good Luck Studying :)
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1) 4/(1/5)
=4 ÷ 1/5
to divide fractions, multiply by the reciprocal/inverse of 1/5
=4 * 5/1
=20
4) (7/9)/7
=7/9 ÷ 7
to divide fractions, multiply by the reciprocal/inverse of 7
=7/9 * 1/7
multiply numerators; multiply denominators
=(7*1)/(9*7)
=7/63
simplify by 7
=1/9
7) (9/10)/6
= 9/10 ÷ 6
to divide fractions, multiply by the reciprocal/inverse of 6
= 9/10 * 1/6
multiply numerators; multiply denominators
= (9*1)/(10*6)
= 9/60
simplify by 3
= 3/20
ANSWER: 1) 20; 4) 1/9; 7) 3/20
Hope this helps! :)