DHS 18.1 - Option 7. Decisions Ryabushko AP

Solve the following problems (1 - 6)

1.7. Of the nine significant figures are three-digit numbers. How many different numbers can be made?

2.7. Of the eight two art books. Find the probability that among the four books taken at random at least one art.

3.7. The computer consists of four blocks. The probability of failure-free operation during the time T of the first unit is 0.4 second - 0.5, the third - 0.6, the fourth - 0.4. Find the probability that have worked for a period of time T a) all four blocks; b) three-block; c) at least three blocks.

4.7. Two machines of the same type are processed items. The likelihood of marriage for machine number 1 is 0.03, for model number 2 - 0.02. Machined parts are formed in one location where the parts machined № 1, twice that of the machine № 2. Find the probability that a) taken at random will be standard item; b) randomly take a standard item made on the first machine.

5.7. In teleatele has 7 TVs. For each TV probability that at the moment it is turned on, it is equal to 0.6. Find the probability that currently includes: a) four of the TV; b) at least one television set; c) at least three televisions.

6.7. The probability of a miss in one shot on target is 0.1. How many shots you need to make to with a probability of 0.9544 it could be argued that the relative frequency slip deviates from the constant probability of the absolute value of not more than 0.03?