The probability of that Mary packed for dinner and the dinner contains no salt is 
Further explanation:
The probability can be obtained as the ratio of favorable number of outcomes to the total number of outcomes.

Given:
John packs
of the dinners, Mary packs
of the dinners and Sue packs the remaining dinners. Of the dinners John packs
do not include a salt packet. If Mary packs the dinner
of the time the salt is omitted. Lastly,
of the dinners do not include salt if Sue does the packing.
Explanation:
The probability of John packs the dinner can be expressed as follows,

The probability of Mary packs the dinner can be expressed as follows,

The probability of Sue packs the dinner can be expressed as follows,

The probability of no salt packet is packed given that the John packs for dinner can be expressed as follows,

The probability of no salt packet is packed given that the Mary packs for dinner can be expressed as follows,

The probability of no salt packet is packed given that the Sue packs for dinner can be expressed as follows,

The probability of that Mary packed for dinner and the dinner contains no salt can be expressed as follows,

The probability can be obtained as follows,

The probability of that Mary packed for dinner and the dinner contains no salt is 
Learn more:
1. Learn more about inverse of the functionhttps://brainly.com/question/1632445.
2. Learn more about equation of circle brainly.com/question/1506955.
3. Learn more about range and domain of the function brainly.com/question/3412497.
Answer details:
Grade: High School
Subject: Mathematics
Chapter: Probability
Keywords: Three worker, fast food, restaurant pack, chicken dinners, John packs, 45% of the dinners, Mary, 25% of dinner, Sue packs remaining, 4% so not include salt, salt packet, salt is omitted, dinner, 2%, 3%, purchased dinner, probability, 0.5625, 0.018, 0.032, 0.15625, 0.005.