<h3><u>The value of x, the first number, is equal to 3.</u></h3><h3><u>The value of y, the second number, is equal to 7.</u></h3>
x + 3y = 24
5x + 3y = 36
We can subtract both equations from each-other to cancel out a variable.
After doing so, we're left with:
-4x = -12
Multiply each term by -1
4x = 12
Divide both sides by 4.
x = 3
Now that we have a value for x, we can solve for y.
Plug this value into the first equation.
3 + 3y = 24
Subtract 3 from both sides.
3y = 21
Divide both sides by 3.
y = 7
Answer:
874×1 = 874
874×10 = 8,740
874×100 = 87,400
874×1,000 = 874,000
Step-by-step explanation:
Answer:
Step-by-step explanation:
x=2
so 7*2= 14
therefore the answer is 14
E = amount she put for Education
CD = amount she put for a Certificate of Deposit.
so, whatever those amounts are, we know that all she got is 70,000 bucks total, so
E + CD = 70000.
how much is three times the CD? well, 3*CD or 3CD.
how much is 10,000 more than that? well 3CD + 10000.
since we know that the amount on Education was 10000 more than three times the CD, then
E = 3CD + 10000.
![\bf \begin{cases} E+CD=70000\implies \boxed{CD}=70000-E\\ E=3CD+10000\\ ------------------\\ E=3\left( \boxed{70000-E}\right)+10000 \end{cases} \\\\\\ E=210000-3E+10000\implies 4E=200000\implies E=\cfrac{200000}{4} \\\\\\ E=50000](https://tex.z-dn.net/?f=%5Cbf%20%5Cbegin%7Bcases%7D%0AE%2BCD%3D70000%5Cimplies%20%5Cboxed%7BCD%7D%3D70000-E%5C%5C%0AE%3D3CD%2B10000%5C%5C%0A------------------%5C%5C%0AE%3D3%5Cleft%28%20%5Cboxed%7B70000-E%7D%5Cright%29%2B10000%0A%5Cend%7Bcases%7D%0A%5C%5C%5C%5C%5C%5C%0AE%3D210000-3E%2B10000%5Cimplies%204E%3D200000%5Cimplies%20E%3D%5Ccfrac%7B200000%7D%7B4%7D%0A%5C%5C%5C%5C%5C%5C%0AE%3D50000)
how much was it invested in the CD? well, CD = 70000 - E.
We have the mean, μ = 20 and the standard deviation, σ = 4
X ≈ N(20, 4²)
We want P(X<15)
Standardising gives
P(X<15) = P(Z<
![\frac{15-20}{4}](https://tex.z-dn.net/?f=%20%5Cfrac%7B15-20%7D%7B4%7D%20)
)
P(X<15) = P(Z< -1.25) ⇒ When the value of the z-score is negative, we will read the value of z<1.25 on the z-table then subtract the answer from 1
P(X<15) = 1 - P(Z<1.25)
P(X<15) = 1 - 0.8944
P(X<15) = 0.1056
Hence, the probability that pizza takes less than 15 minutes to be delivered is 0.1056 = 10.56%