Let's call your speed "a"
her walking speed is then "2a"
and her friend's scooter speed is 10 a
let's also call the distance you need to walk "d"
so the time (t)you need is:
d/t=a
t=d/a
and her time is:
t=
(half a distance with the speed of 2a and half a distance (d/2) with the distance of 10 a
now we count (we know that her time is 30 minutes)
30=
//multiply by 20a
600a=
600a=6d/divide by 6
100a=d
Now, in order to calculate your time we need to calculate:
t=d/a
but we know how much is d now!
t=
=100
which means that you need 100 minutes, or 1 h 40 minutes!!!
Step-by-step explanation:
the introduction of a fraction tells us that we are dealing with multiplications, and therefore a geometric sequence (where every new term is created by multiplying the previous term by a constant factor, the ratio r).
I think your teacher made a mistake, or you made one when typing the question in here.
there is no factor r that creates
15×r = 9
and
9×r = 5/27
it would mean that
15 × r² = 5/27
r² = 5/27 / 15 = 5/27 × 1/15 = 5/405 = 1/81
r = 1/9
but 15 × 1/9 = 5 × 1/3 = 5/3 is NOT 9
and 9 × 1/9 = 9/9 = 1 is NOT 5/27
so, this can't be right.
on the other hand
15 × r = 9
r = 9/15 = 3/5
and then
9 × 3/5 = 27/5
so, either the sequence should have been
15, 5/3, 5/27
or (and I suspect this to be true)
15, 9, 27/5
under that assumption we have
s1 = 15
r = 3/5
sn = sn-1 × r = s1 × r^(n-1) = 15 × (3/5)^(n-1)
s10 = 15 × (3/5)⁹ = 15 × 19683/1953125 =
= 3 × 19683/390625 = 59049/390625 =
= 0.15116544 ≈ 0.151
Answer:
The measure of the fourth angle = 137.1°
Step-by-step explanation:
Let x = the measure of the fourth angle
Sum of all 4 interior angles in a quadrilateral equal 360°
so
x + 23.5° + 99° + 100.4° = 360°
x + 222.9° = 360°
x = 360° - 222.9°
x = 137.1°
Answer:
Θ = 46°
Step-by-step explanation:
the angle between a tangent and a radius at the point of contact is 90° , so
∠ ABO = 90°
since OB = OD ( radii of circle ) then Δ BOD is isosceles and
∠ OBD = ∠ ODB = 22°
the exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.
∠ AOB is an exterior angle of the triangle , then
∠ AOB = 22° + 22° = 44°
the sum of the 3 angles in Δ AOB = 180° , then
Θ + 44° + 90° = 180°
Θ + 134° = 180° ( subtract 134° from both sides )
Θ = 46°
The answer is 75! Explanation, use the distance formula
