Answer:
Rs 19.20
Step-by-step explanation:
Buying price = Rs 20
Profit = 20% = 0.20 × 20 = Rs 4
Selling price = buying price + profit = Rs 20 + Rs 4 = Rs 24
He wants to make a 25% profit.
Let's say he should buy the pen at Rs 'a' in order to make that amount of profit.
∴ a + = 24
1.25a = 24
a =
So he should buy the pen at Rs 19.20
a. <-13/2,-13/2>
<h2>Step-by-step explanation:</h2>The projection of a vector u onto another vector v is given by;
=
----------------(i)
Where;
u.v is the dot product of vectors u and v
|v| is the magnitude of vector v
Given:
u = <-6, -7>
v = <1, 1>
These can be re-written in unit vector notation as;
u = -6i -7j
v = i + j
<em>Now;</em>
<em>Let's find the following</em>
(i) u . v
u . v = (-6i - 7j) . (i + j)
u . v = (-6i) (1i) + (-7j)(1j) [Remember that, i.i = j.j = 1]
u . v = -6 -7 = -13
(ii) |v|
|v| =
|v| =
<em>Substitute these values into equation (i) as follows;</em>
=
=
This can be re-written as;
=
=