4th grade math
posted by Kristin on .
Find a rule that gives the third number from the first two numbers. Fill in the blanks.....10, 4, 5, ? 15, 7,7, ? 19,9,?

Is there a number missing in the last one?
posted by Kristin on .
Find a rule that gives the third number from the first two numbers. Fill in the blanks.....10, 4, 5, ? 15, 7,7, ? 19,9,?
Is there a number missing in the last one?