We know that C is 385, so we can plug that in to get the equation 385=15n+85. To find the number of watches, we have to solve for n.
To do that we have to...
385=15n+85
First subtract both sides of the equal sign by 85 (because we need to do the opposite)
300=15n (because 85-85 is zero, so we eliminated that, and 385-85 is 300)
Now we divide both sides of the equal sign by 15 (again, opposites)
20=n (because 15n/15 leaves us with n since both 15s cancel out, and 300/15 is 20)
So the number of watches made were 20.
Answer:
c = -54
Step-by-step explanation:
Solve for c:
(7 c)/8 - 3 (c/8 - 7) = -6
Put each term in c/8 - 7 over the common denominator 8: c/8 - 7 = c/8 - 56/8:
(7 c)/8 - 3 c/8 - 56/8 = -6
c/8 - 56/8 = (c - 56)/8:
(7 c)/8 - 3(c - 56)/8 = -6
(7 c)/8 - (3 (c - 56))/8 = (7 c - 3 (c - 56))/8:
(7 c - 3 (c - 56))/8 = -6
-3 (c - 56) = 168 - 3 c:
(7 c + 168 - 3 c)/8 = -6
7 c - 3 c = 4 c:
(4 c + 168)/8 = -6
Multiply both sides of (4 c + 168)/8 = -6 by 8:
(8 (4 c + 168))/8 = -6×8
(8 (4 c + 168))/8 = 8/8×(4 c + 168) = 4 c + 168:
4 c + 168 = -6×8
8 (-6) = -48:
4 c + 168 = -48
Subtract 168 from both sides:
4 c + (168 - 168) = -168 - 48
168 - 168 = 0:
4 c = -168 - 48
-168 - 48 = -216:
4 c = -216
Divide both sides of 4 c = -216 by 4:
(4 c)/4 = (-216)/4
4/4 = 1:
c = (-216)/4
The gcd of -216 and 4 is 4, so (-216)/4 = (4 (-54))/(4×1) = 4/4×-54 = -54:
Answer: c = -54
First deal there are 14 red and 6 black so fraction of red = 14/20 or 0.7
second deal there are 20 red and 10 black so fraction of red = 20/30 or 0.67
0.67 is closer to 1/2 that 0.7 so
c is the correct choice
Answer:
tanC = 
Step-by-step explanation:
tanC =
=
= 