I think you meant to type
4(n)-5=7.
4n = 7 + 5
4n = 12
n = 12/4
n = 3
Using the Sine Rule:-
20 /sin 45 = BC / sin 30
BC = 20 sin 30 / sin45
= 20 * 1/2 / 1 / sqrt2
= 20 * 1/2 * sqrt2
= 10 sqrt2 answer
The first solution contributes 0.78*1 = 0.78 L of acid.
The second contributes 0.64*6 = 3.84 L of acid.
There will be 7 L total of the new solution, and 3.84 + 0.78 = 4.62 total L of acid in it. So the new solution has a concentration of 4.62/7 = 0.66, or about 66%.
Answer:
Step-by-step explanation:
<em>Let the number be x </em>
So,
=> The sum of number and 15 is x + 15
=> Three times will be 3(x+15)
<u>Given that</u> it equals 24
<u>So, the given condition is:</u>
3(x+15) = 24
<em>Resolving Parenthesis</em>
3x + 45 = 24
<em>Subtracting 45 to both sides</em>
3x = 24 - 45
3x = -21
<em>Dividing both sides by 3</em>
x = -7
Its a simple equatioon,
First write the information that is given to you (as an equation) 14+x=17
Since you have a variable that is "x" you need to take it out of the equation as x=17-14 and put the 17 (that is the result) and then since you're adding 14, at the other side you'll substract it, finally do the opperation and you get your result that is x=3
