Beth and Korey have both been saving their pocket money. The ratio of the amount Beth has saved to the amount Korey has saved is 2 : 7 Korey has saved £40 more than Beth. Work out the amount of money Beth has saved.
Answers
Answer:
The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of an object's speed and direction of motion (e.g. 60 km/h to the north).
Step-by-step explanation:
The measure of central angle is 90 degrees.
Step-by-step explanation:
Given : Sector perimeter is 25 cm and radius of the circle is 7 cm.
To find : Measure of central angle of the sector?
Solution :
We know, The perimeter of sector is defined as
P=l+2rP=l+2r
where, l is the length arc and r is the radius.
P=25 cm , r=7 cm
25=l+2(7)25=l+2(7)
25=l+1425=l+14
l=25-14l=25−14
l=11l=11
So, The length of the arc is 11 cm.
Angle subtended by a circle is 360 degrees
Circumference of circle is given by,
\begin{gathered}C=2\pi r\\C=2\times \frac{22}{7}\times 7\\\\C=44cm\end{gathered}
C=2πr
C=2×
7
22
×7
C=44cm
Angle subtended by arc is given by,
\theta = 360\times \frac{l}{C}θ=360×
C
l
\theta = 360\times \frac{11}{44}θ=360×
44
11
\theta =\frac{360}{4}θ=
4
360
\theta =90^\circθ=90
∘
Therefore, The measure of central angle is 90 degrees.