A-A+
令a=11×65+13×66+15×67+17×68+19×69+21×70+23×7111
问题详情
令a= a=11×65+13×66+15×67+17×68+19×69+21×70+23×7111×64+13×65+15×66+17×67+19×68+21×69+23×7011×65+13×66+15×67+17×68+19×69+21×70+23×71 11×64+13×65+15×66+17×67+19×68+21×69+23×70.若将a化成小数,则a的百分位数字是______.
参考答案
=11×64+13×65+15×66+17×67+19×68+21×69+23×70+11+13+15+17+19+21+2311×64+13×65+15×66+17×67+19×68+21×69+23×70
=1+11+13+15+17+19+21+2311×64+13×65+15×66+17×67+19×68+21×69+23×70
所以,1+11+13+15+17+19+21+23(11+13+15+17+19+21+23)×70<a<1+11+13+15+17+19+21+23(11+13+15+17+19+21+23)×64
所以,1+170<a<1+164,即:1.0143<a<1.0157.
所以a的百分位数字是1.
故答案为:1考点: