Equations Unknown Add Sub

Print: Ages 10–11 · 1–2 min · Core · Missing addend · Independent practice · Numeric response

Watch: Watch whether the learner enters 20,000 before opening support and checks it in the inline blank. A correct first check shows that every shown addend was accounted for and the remaining place value was matched.

Misread: A response of 20 or 2,000 points to a place-value shift; 20,305, 20,300, or 20,005 shows that a shown addend was counted inside the blank. Copying 6,020,305 or 6,000,000 means the learner treated the blank as the whole or repeated a known part.

Curriculum: This task uses place-value decomposition and inverse addition/subtraction to find one missing addend in an exact equality. It scores one multi-digit integer and verifies it by substitution, with the seven-digit magnitude treated as an upper-primary capstone.