Ages 7–8🧮 Mathematics9 verified questions on this shelf

Mental addition and subtraction (age 7+)

Mentally add and subtract a three-digit number and ones

Try three questions

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Question 1 of 3

A library shelf holds 584 books. The librarian puts 6 more books on the shelf. After the addition, which statement about the digits of the new total is correct?

Question 2 of 3

What is 642 − 7?

Question 3 of 3

A baker puts 7 more cupcakes on a tray that already has 398 cupcakes. How many cupcakes are now on the tray?

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A free account keeps practising Mental addition and subtraction (age 7+) with 9 verified questions, tracks the Skill as it blooms, and connects a real teacher when you want one. Every student account needs a parent's email first.

Skill names and descriptions include the Marble Skill Taxonomy © Generative Spark, Inc. (withmarble.com), licensed under ODbL 1.0 (database) and CC BY-SA 4.0 (content). Practice questions are GlowGrades's own, each checked by independent verifiers that must agree before a child ever sees it.