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The Special Double: 5+5
The double 5 plus 5 is one of the most important math facts you will ever learn. Hold up both of your hands and count all your fingers: 5 on one hand and 5 on the other. That is 10 fingers altogether! 5 plus 5 equals 10. This fact is extra special because 10 is a big deal in math. Our whole number system is built on groups of 10. When you know that 5 plus 5 is 10, you have a superpower for solving lots of other problems.