90 juniors took different SAT-II tests. 40% more students took Chemistry than History, and 50% more students took Math than Chemistry. How many students took each test?___ Students took History Test___Students took Chemistry Test___Students took Math Test

Answer:20 Students took History Test 28 Students took Chemistry Test 42 Students took Math TestStep-by-step explanation:Letx ----> Students that took History Testy ---> Students that took Chemistry Testz ----> Students that took Math Testwe know thatx+y+z=90 -----> equation Ay=1.40x -----> x=y/1.40 -----> equation Bz=1.50y -----> equation Csubstitute equation B and equation C in equation A and solve for y(y/1.40)+y+1.50y=90Multiply both sides by 1.40y+1.40y+2.1y=1264.5y=126y=28Find the value of xx=y/1.40 -----> x=28/1.4=20Find the value of zz=1.50y ----> z=1.50(28)=42therefore 20 Students took History Test 28 Students took Chemistry Test 42 Students took Math Test