Why dose it take 4 copies of 1 tenth to equal 2 copies of 1 fifth

Which term describes the point where the perpendicular bisectors of the three sides of a triangle intersect?

Emmanuel added 888 links per minute to his chain mail. allesia started 202020 minutes after emmanuel and added 131313 links per minute to her chain mail. how long had emmanuel worked when allesia caught up to him, and how many links had he added?

7x^2-9x+5=0 find the discriminant and number of real solutions