Answer:
a) 8x + 5x = 13x
b) 9f + 10f - 12f = 7f
Step-by-step explanation:
For part b, just solve from left to right normally, since adding and subtracting are inverse operations. (Inverse operation; meaning they are opposites of each other.)
So 9 + 10 = 19, and 19 - 12 = 7.
Hope this helps you :)
<h2><em><u>Solution</u></em> : </h2>
let the last number be x
we know,

So,





therefore, the last number is 10.
To find surface area, we can use the equation:
SA=2lw+2wh+2lh, where:
l=10 in
w=3 in
h=7 in
SA=(2)(10)(3)+(2)(3)(7)+(2)(10)(7)
SA=60+42+140
SA=242 in²
Lets take away 2 white chips...
8 black and 4 white...total of 12 chips
P(black) = 8/12 = 2/3
remove 2 white chips <==