Select the statement where the value of the unknown number is 5.5.

answer choices

a number divided by 2 is 5.5.

2 divided by a number is 2.75.

a number divided by 2 is 2.75.

a number divided by 2.75 is 5.5.

Initially 100 milligrams of a radioactive substance was present. after 6 hours the mass had decreased by 4%. if the rate of decay is proportional to the amount of the substance present at time t, find the amount remaining after 24 hours. (round your answer to one decimal place.)

Which expression gives the area of the triangle shown below

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.