P – AS – OE12

The estimated sum of two numbers is 500. What could the two numbers be?

P – AS – OE13

The estimated sum of two numbers is 900. What could the two numbers be?

P – AS – OE14

Six different digits are used to make two 3-digit numbers. What is the sum of these two numbers?

P – AS – OE15

Four different digits are used to make two 2-digit numbers. What is the difference between these two numbers?

P – AS – OE16

How does knowing what 9 + 4 equals help with solving 13 – 5?

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