Luis is finding 5 because 9 minus 6 is 3. 3 plus 2 equal 5 easy
1.68 mm per year for 1.5 years could be rewritten as
(2.00-0.32) mm per year for 1.5 yrs.
Multiply: (1.5 yrs)(2.00-0.32)(mm/yr) = 3 mm + 0.48 mm = 3.48 mm
This approach makes use of the distributive property of multiplication.
F=9/5c+32
-31=9/5c+32
-63=9/5c
-35=c
135.78 rounded to the nearest tenth is 135.8.