You plate a unit sample of progeny phages on E. coli strain B and observe 30,000 plaques. How many plaques total were produced by progeny phages in a unit sample?

30, 000 plaques.

Explanation:

Plaques may be defined as the clear zones or spots that indicates the lysis of the bacteriophages. These plaques are useful to count the number of progeny phages.

The formula used to calculate the phage is as follows;

Plaques progeny = [Number of plaques observe/(Dilution factor x Volume of diluted virus)]

Since, in the given question the dilution factor and volume is not given and it can be taken as unity.

Plaques progeny = 30, 000 / ( 1 x 1)

Plaques progeny =  30, 000.

Thus, the answer is 30, 000.