Add them all together: 36
Hockey card probability: 4/36
Simplify: 1/9
Hope you won't be turned off by a correction, but we really need to use the symbol " ^ " to denote exponentiation.
Thus, we have x^2 = 100
Taking the square root of both sides, we get x = plus or minus 10. Verify, please, that both x = -10 and x = +10 satisfy the given equation.
1/5 of a foot
Simply subtract the height of Pancho’s sandcastle (3/5 of a foot) minus the height of his sister’s sandcastle (2/5 of a foot) to find a difference of 1/5 of a foot, meaning Pancho’s sandcastle was 1/5 of a foot taller than his sister’s sandcastle.
One equivalent fraction for 4/21 could be 8/42.