Answer:
The last one
Step-by-step explanation:
FInd a common demominator which is 20 and multiply both so it turns into 4 19/20
The probability any one system works is 0.99
So the probability of any one system failing is 1-0.99 = 0.01, so basically a 1% chance of failure for any one system
Multiply out the value 0.01 with itself four times
0.01*0.01*0.01*0.01 = 0.000 000 01
I'm using spaces to make the number more readable
So the probability of all four systems failing is 0.00000001
Subtract this value from 1 to get
1 - 0.00000001 = 0.99999999
The answer is 0.99999999 which is what we'd expect. The probability of at least one of the systems working is very very close to 1 (aka 100%)
Is the answer 240.is that one of your options
Answer:A
Step-by-step explanation:
the answer is A
Answer:
58
Step-by-step explanation:
1. let x be the unknown number
2. make an expression
x + 26/12 = 7/1
3. cross multiply
x +26 × 1 = x + 26
12 × 7 = 84
x + 26 = 84
4. move variables on one side and numbers on other side of the equal sign
x + 26 = 84
- 26 -26
x = 58