问题
选择题
已知:N=220×518,则N是( )位正整数.
A.10
B.18
C.19
D.20
答案
∵N=220×518,
=22×218×518
=4×(2×5)18
=4×1018.
∴N是19位正整数.
故选C.
已知:N=220×518,则N是( )位正整数.
A.10
B.18
C.19
D.20
∵N=220×518,
=22×218×518
=4×(2×5)18
=4×1018.
∴N是19位正整数.
故选C.