How many times longer was Claire's time to mow all the lawns last week than this week? Explain. Claire mowed 5 lawns last week. She mowed each lawn in 7/18 hour. She mowed the same lawns this week in 5/18 hour each using her new lawn mower. How many times longer was Claire's time to mow all the lawns last week than this week? Explain.

10/18 Hours

Step-by-step explanation:

Clair Mowed 5 lawns last week

Time Taken last week= 5×7/18

=35/18 Hours

Clair Mowed 5 lawns this week

Time taken this week=5×5/18

=25/18 Hours

Clair takes: 35/18 - 25/18 = 10/18 times longer.

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

77

step-by-step explanation: