5/6 x 2 1/3 is 10/3 how can you tell that his answer is wrong need plz.

Step-by-step explanation:

first it would be easier to change2 1/3 into an improper fraction.

so 2 x 3 + 1 = 7    so it would be 7/3

5/6 x 7/3 = 35/18

and 35/18 is definitely not 10/3

when you multiply fractions, times the numerator together, and the denominator together

5x2=10

6x2=12

1x4=4

3x4=12

4x10=40     40/12=4/12

3+2=5

=5 4/12

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