Y^8/y^5
When multiplying exponents with the same base, you add the exponents
210 because 209 is closer to 210 than to 200
What pair should it be to
Doubles are adding the same number together, as with 5+5=10.
With doubles +1, the numbers must be in beside each other in counting order going up or down (ex: 4, 5, 6 and 9, 8, 7). Do the SMALLEST number, double it, then add one. So, 9+8 would be 8+8=16, +1=17. You must know your doubles facts before this strategy is useful.