8. A bag contains 72 toffees. How many toffees can be stored in 122 such bags? Estimate the number of toffees to nearest tens. 9.The working of a metro station is controlled by 28 persons. Estimate the number of persons required to control the working of 88 such stations to the nearest tens.

8.) 8,780 toffees can be stored in 122 such bags.

9.) 2,460 people are required to control the working of 88 such stations.

Step-by-step explanation:

QUESTION 8:

We know that there are 72 toffees per bag

So if we want to know how many toffees can be stored in 122 such bags:

72 x 122 = 8,784

ROUND IT TO THE NEAREST TENS:

Look at the digit to the right of the tens place: 8,784–>4. 4 and below means that the digit will be repkaced by 0 and the tens place remains the same.

So 8,784 rounded to tens is 8,780

Tye answer for question 9 is

2,460 (do the same thing)

  n=   0.0000 - 0.3750 i  

  n=   0.0000 + 0.3750 i

step-by-step explanation:

one of these should be correct

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12