解:0.138乘以100000等于( 13800 ) ∵已知需求出0.138乘以100000等于多少 X × Y = Z ∴0.138乘以100000 = 0.138 × 100000 = 138/1000 × 100000 = 69/500 × 100000 = 13800 答:0.138乘以100000等于13800