(126) times (1/2 to the x/11 power) = 15% times 126
(1/2) to the x/11 power = 0.15
Take the log of both sides :
(x/11) times log(1/2) = log(0.15)
Multiply both sides by 11 :
'x' times log(1/2) = 11 x log(0.15)
Divide both sides by " log(1/2) " :
x = 11 x log(0.15)/log(1/2) = <em><u>30.107 years</u></em> (rounded)
That's the time it takes for <em><u>any-size</u></em> sample of this substance
to decay to 15% of its original size.
Answer:
10,9.75,9.5,9.25,9, 8.75 , 8.5, 8.25, 8...
Step-by-step explanation:
Subtract 0.25 from each to find the next number
Answer:
If it took the motorcycle 2 hours to cover 20km, then the average speed is 10km per hour.
Speed is equal to distance over time. So 20km divided by 2 hours is 10 km per hour.
The equation representing when the two planes would be at the same altitude is 9x=486
<h3>In terms of mathematics, what is an equation?</h3>
Equation: A declaration that two expressions with variables or integers are equal. In essence, equations are questions, and attempts to systematically identify the solutions to these questions have been the driving forces behind the creation of mathematics.
From (a) we get that: Altitude of Plane A = 990-18x
Altitude of Plane B = 1476-27x
make 890 - 18x = 1476-27x
-18x+27 x = 1476-890
9x=486
X= 54
so pass 54 seconds will the two plane at the same altitude.
To learn more about equations from given link
brainly.com/question/25678139
#SPJ9
Answer:
20°
Step-by-step explanation:
40°, 70° and 90° are the measures of the three angles of the quadrilateral.
Measure of fourth angle of the Quadrilateral
= 360° - (40° + 70° + 90°)
= 360° - 200°
= 160°
Measure of angle 1 will be equal to the measure of the linear pair angle of 160° as they are corresponding angles.
Thus,
Alternate method:
![m\angle 1 = 180\degree- [360\degree-(40\degree+70\degree+90\degree)]](https://tex.z-dn.net/?f=m%5Cangle%201%20%3D%20180%5Cdegree-%20%5B360%5Cdegree-%2840%5Cdegree%2B70%5Cdegree%2B90%5Cdegree%29%5D)
![\implies m\angle 1 = 180\degree- [360\degree-200\degree]](https://tex.z-dn.net/?f=%5Cimplies%20m%5Cangle%201%20%3D%20180%5Cdegree-%20%5B360%5Cdegree-200%5Cdegree%5D)
