For each coin, there are <u>2 outcomes</u>, heads (H) or tails (T), so for the <u>3 coins</u>, the number of outcomes are:
2 x 2 x 2 = <u>8 outcomes:</u>
HHH / HHT / HTH / THH / TTT / TTH / THT / HTT
Out of all these outcomes, there are <u>3 ways</u>, we get exactly 2 Heads:
HHT / HTH / THH
So, the probability of exactly 2 coins landing on Heads is 3/8, or 0.375
#1) x-8= -12
#2) 15+k= 2
#3) x/-7= -20
#4) (5/8)(x)= -20
The / in #2 means to divide and the ( ) mean to multiply
