Question 712175
D=2R
D-10+2R-10=40
2R-10+2R-10=40
4R-20=40
4R=40=20
4R=60
R=60/4
R=15 AGE OF RICK NOW.
D=2*15=30 AGE OF DAVE NOW.
PROOF:
30-10+2*15-10=40
20+30-10=40
50-10=40
40=40