Answer:
Part a) Tim has completed the greater amount of work
Part b) They have completed together
of the project or
of the project
Step-by-step explanation:
Part a) Who has completed the greater amount of work?
we have
Jaime has 5/11 of a project completed
Tim has 7/13 of a project completed
Multiply 5/11 by 13/13 and 7/13 by 11/11
so
Jaime --->
Tim ---> 
Remember that
When fractions have the same denominator, the larger fraction is the one with the larger numerator

therefore
Tim has completed the greater amount of work
Part b) How much of the project have they completed together?
we have that
Jaime has 65/143 of a project completed
Tim has 77/143 of a project completed
Sum the fraction of the project completed by Jaime plus the fraction of the project completed by Tim

Convert to percentage
Multiply by 100
