Harper has a mask collection of 400 masks. She keeps 21% of the masks on her wall. How many masks does she keep on her wall?

Aquadrilateral has exactly one pair of parallel sides. which name best describes the figure?

Paul’s car is 18 feet long. he is making a model of his car that is 1/6 the actual size. what is the length of the model?

Jessa bought a yoyo from a company that claims that, with each retraction, the string rolls up by 60% of the original length. she sets up a tape measure and throws the yoyo 3 times. her data are charted below. throw length of string (feet) 1 3 2 1.8 3 1.08 jessa wants to find the sum of the length of string after 10 throws. what is the sum of the lengths, rounded to the nearest hundredth?