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Here are some tips for Missing Operator, which aligns with Florida state standards:

Missing Operator

To master this topic, you need to first master the topics:

There are two ways to solve missing operator problems.

First Method: Brute force

 Supply the missing operator.       10 = 3 7 Supply the missing operator. 15 5 = 3 Try: Try: 10 = 3 + 7? Yes! 15 + 5 = 3? No 10 = 3 - 7? No 15 - 5 = 3? No 10 = 3 × 7? No 15 × 5 = 3? No 10 = 3 ÷ 7? No 15 ÷ 5 = 3? Yes! Answer: Answer: 10 = 3 7 15 5 = 3

Second Method: Using logic

Consider the problem in terms of three numbers: two operands and one answer.
 operand 1 operator operand 2 = answer 3 × 7 = 21

Supply the missing operator.
3 = 12 9
Supply the missing operator.
6 3 = 18
Step 1: Compare operand 1 and answer
If operand 1 is larger than the answer,
then the operation is either subtraction or division.

Since 12 > 3, the operation is either subtraction or division.
If the operand 1 is smaller than the answer,
then the operation is either addition or multiplication.

Since 6 < 18, the operation is either addition or multiplication.
Step 2: Try the two operators

 3 = 12 - 9? Yes! 3 = 12 ÷ 9? No
 6 + 3 = 18? No 6 × 3 = 18? Yes!
Answer: 3 = 12 9 6 3 = 18

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