What go in the blanks?

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

Me complete this proof! prove that a quadrilateral is a square. me with the steps for this proof.

Fred has a spinner that is split into four equal sections: red, blue, green, and yellow. fred spun the spinner 688 times. which of the following would be a good estimate of the number of times the spinner lands on the green section? a. 269 b. 603 c. 344 d. 189