Answer: He made $90 last week.
Assumption :
Let, Luis made $X last week.
He made $72 this week which is 80% of $X that he made last week
⇒ X * 80% = 72
⇒ X * 80/100 = 72
⇒ X = (72 * 100)/80
⇒ X = 90
Therefore, he made $90 last week.
To remember :
While solving this type of problems, be careful to understand which one of last time and current time is not given; just assume that one and input other conditions, the problem will be solved.
Answer:
x = lillies
y = tulips
x + y = 13
1.25x + .90y = 14.85
-1.25x - 1.25y = -16.25
1.25x + .90y = 14.85
-0.35y = -1.40
y = 4 tulips
x + 4 = 13
x = 9 lillies
(9 lillies, 4 tulips)
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
loudness depends on the amplitude or height of the sound waves
Answer:
a₈ = - 1 / 128
Step-by-step explanation:
Given:
First four terms of the sequence
a₁= 1, a₂= - 1/2, a₃= 1/4 and a₄= -1/8
First we recognize that this is a geometric series (sequence) and we must calculate quotient q.
q = a₂/a₁ = a₃/a₂ = (-1/2)/1 = (1/4)/(-1/2) = - 1/2
q = - 1/2
Formula for calculating n-th term is:
aₙ = a₁ · qⁿ⁻¹
According to this:
a₈ = 1 (-1/2)⁷ = - 1/ 128
God with you!!!
Hey guys it equals 12 alight