问题 解答题 26+39=7.8-3.6=1.2+0.9=24×3=52×0.4=21.7÷0.7=13-16=14+38= 答案 26+39=65,7.8-3.6=4.2,1.2+0.9=2.1,24×3=72,52×0.4=20.8,21.7÷0.7=31,13-16=16,14+38=58.