140 tiles with an area of 36 square decimeters are just finished. How many tiles do you need if you switch to a 3-decimeter-long tile

140 tiles with an area of 36 square decimeters are just finished. How many tiles do you need if you switch to a 3-decimeter-long tile

Set X blocks
36:(3×3)=x:140
9x=36×140
x=36×140÷9
x=560