If a number becomes 2.5 times smaller, by what percent was it decreased?

Which expression is equivalent to 4 square root 6 divided by 3 root 2

Pls if a cow has a mass of 9×10^2 kilograms, and a blue whale has a mass of 1.8×10^5 kilograms, which of these statements is true?

Karen will divide her garden into equal parts. she will plant corn in 8/12 of the garden. what is the lowest number of parts she can divide her garden into?