Answer:
number of dimes is 8
number of quarters is 15
Step-by-step explanation:
let 'd' = number of dimes
let 'd+7' = number of quarters
.10d + .25(d + 7) = 4.55
.10d + .25d + 1.75 = 4.55
.35d = 2.80
d = 8
q = 7 + 8
an = a1r^(n-1)
a5 = a1 r^(5-1)
-6 =a1 r^4
a2 = a1 r^(2-1)
-48 = a1 r
divide
-6 =a1 r^4
---------------- yields 1/8 = r^3 take the cube root or each side
-48 = a1 r 1/2 = r
an = a1r^(n-1)
an = a1 (1/2)^ (n-1)
-48 = a1 (1/2) ^1
divide by 1/2
-96 = a1
an = -96 (1/2)^ (n-1)
the sum
Sn = a1[(r^n - 1/(r - 1)]
S18 = -96 [( (1/2) ^17 -1/ (1/2 -1)]
=-96 [ (1/2) ^ 17 -1 /-1/2]
= 192 * [-131071/131072]
approximately -192
Answer:
Fraction: 23/100
Decimal: .23
Percent: 23%
Step-by-step explanation:
Because there are 23 squares shaded out of 100.
<span>So we have a problem with two unknows and one equation. We have to express one over the other like this: 7a - 2b = 5a + b. First we separate one kind on the left side and the other kind on the right side: 7a - 5a = b + 2b. Then: 2a = 3b. Now we divide both sides by 2 and get: a= 3b/2.</span>
B5 = -1 x (2 ^ 5 - 1)
B5 = -1 x (2 ^ 4)
B5 = -1 x 16
B5 = -16