There are 28 couples at a party Each person shakes hands with every other person,
except their own spouse.
When the party is over, Mr. Smith asks each attendant how
many hands they shook and everyone tells him a different number.
How many hands did Mr. Smith shake?

Mr. Smith shook 54 hands

Step-by-step explanation:

28 couples are a group of two people,so, 28 *2 equals to 55, subract his spouse and it will be 54

walter needs to make at least 5 more cookies but no more than 40. 5 ≤ x ≤ 40

step-by-step explanation:

20 ≤ x + 15 ≤ 55

subtract 15 from all parts

20-15 ≤ x + 15-15 ≤ 55-15

5 ≤ x ≤ 40

this means how many more cookies he has to make

walter needs to make at least 5 more cookies, but no more than 40 cookies; 5 ≤ x ≤ 40

b. 153 students do not participate in sports and seventy-five 12th graders were surveyed