问题
填空题
2+4+6+8+10+12+14+16+18=______×______.
答案
2+4+6+8+10+12+14+16+18,
=(2+18)×9÷2,
=20×9÷2,
=10×9.
故答案为:10,9.
2+4+6+8+10+12+14+16+18=______×______.
2+4+6+8+10+12+14+16+18,
=(2+18)×9÷2,
=20×9÷2,
=10×9.
故答案为:10,9.