(a)
= 4n + 8
(b) row 13 has 60 seats
(a)
the sequence of seats is an arithmetic sequence whose n th term is
=
+ (n - 1 )d
where
is the first term and d the common difference
here the sequence is 12, 16, ....
with
= 12 and d = 16 - 12 = 4, thus
= 12 + 4( n - 1 ) = 12 + 4n - 4 = 4n + 8
(b)
calculate the number of rows n when 60 seats
solve 4n + 8 = 60 ( subtract 8 from both sides )
4n = 52 ( divide both sides by 4 )
n = 13 ← number of rows
1/4 is the amount of girls in 8th grade
hope its not too late
Answer:
1. J because it's a straight line
2. 225
however I only got 4 marks not 5.
Step-by-step explanation:
Answer:
We have to add 1.86 L of water to make the solution 7% saline.
Step-by-step explanation:
The concentration of a saline solution is given by
C(x) = 
where x represents the amount of water used to dilute the solution.
We have to find how much water must be added to obtain a solution that is 7% saline.
If we see the equation we notice that as we add the value of x, the concentration of the solution decreases.
Here C(x) = 0.07
0.07 = 
Rearranging,
1 + x = 
1 + x = 2.86
x = 1.86 L
We have to add 1.86 L of water to make the solution 7% saline.