Apples = X
Pears = Y
3x+2y = 0.60
pears cost 2X-0.05 replace Y with this:
3X +2(2x-0.05) = 0.60
Simplify:
3X + 4X-0.10 = 0.60
Simplify:
7X -0.10 = 0.60
Add 0.70 to each side:
7X = 0.70
Divide both sides by 7:
X = 0.70 / 7
X = 0.10
Apples cost 0.10 each.
Pears cost 2x-0.05 = 2(0.10) - 0.05 = 0.20 - 0.05 = 0.15 each
As you can see, this is a multiplication root.
y = 4 · x
x = 7 · 3
So solve for x first to solve for y.
x = 7 × 3
x = 21
y = 4 · x
y = 4 × (21)
y = 84
Answer:
Answer is B. Y=31
Step-by-step explanation:
4y + 228 = 352
(4)(y) = 352 -228
y = 124/4
y = 31
Answer:
perez has 28 student . and , according to this questions ,5 / 7 of those student participants in school sports.Thus 20 students participate in school sport .
Answer:
0.0062
Step-by-step explanation:
Let X be the random variable blood pressure.The information we are given are
mean blood pressure=μx=120
standard deviation blood pressure=σx=8
we have to find P(mean bp>122)=P(xbar>122).
P(Xbar>122)=P(xbar-μxbar/σxbar>122-μxbar/σxbar)=P(Z>122-μxbar/σxbar)
Now, we have to find μxbar and σxbar. We know that
μxbar=μx
σxbar=σx/sqrt(n).
So, μxbar=μx=120
σxbar=σx/sqrt(n)=8/sqrt(100)=0.8
P(Xbar>122)=P(Z>122-120/0.8)=P(Z>2.5)=P(0<z<∞)-P(0<z<2.5)
From normal distribution table P(0<z<2.5)=0.4938 and we know that P(0<z<∞)=0.5. So,
P(Xbar>122)=0.5-0.4938=0.0062
There is 0.62% chance that the mean blood pressure of 100 people will be greater than 122