70% of all us households have vcrs. in a random sample of 15 households, what is the probability that the number of households with vcrs is between 10 and 12, inclusive?

Therefore the probability of 10 - 12 inclusive = 0.20613 + 0.21862 + 0.17004  

= 0.59479  

+ 59.5% to one place of decimals

Step-by-step explanation:

P(exactly 10) = 15C10 * (0.70)^10 * (0.30)^5  

=15! / (10! * 5!) * (0.70)^10 * (0.30)^5  

= (15*14*13*12*11) /(5*4*3*2*1) * (0.70)^10 * (0.30)^5  

= 0.20613  

P(exactly 11) = 15C11 * (0.70)^11 * (0.30)^4  

= (15*14*13*12)/(4*3*2*1) *(0.70)^11 *(0.30)^4  

= 0.21862  

P(exactly 12) = 15C12 * (0.70)^12 * (0.30)^3  

= (15*14*13)/(3*2*1) * (0.70)^12 * (0.30)^3  

= 0.17004  

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116