多10或少10

能不用数数，心算出一个给定的两位数多10或少10是多少。

Mentally find 10 more or 10 less than a given two-digit number without counting

学习证据 / Evidence

• 看到56，能马上说出66比56多10，46比56少10。
• 能解释加10会使十位数字增加1。
• 能不用手指或逐个数数，答出“比73多10”是多少。

• Given 56, quickly say 66 is 10 more and 46 is 10 less
• Explain that adding 10 increases the tens digit by 1
• Answer '10 more than 73' without using fingers or counting on

评估问题 / Assessment

{{name}}能不用一个一个数，快速说出比43多10或比71少10的数是多少吗？

Can {{name}} quickly tell you what is 10 more than 43 or 10 less than 71 — without counting up or down one at a time?