What is the lcd of 4 7/9 and 2 2/3?

Can someone me my sister? she is in third grade. 50 points and brainlist! ones that are not answered. plz and thx!

What should be done to solve the equation? x+14=21 add 14 to both sides of the equation. subtract 14 from the left side of the equation. add 14 to the left side and subtract 14 from the right side of the equation. subtract 14 from both sides of the equation.

Simplify each expression. use positive exponents. show work . (x –2 y –4 x 3 ) –2