My answer is 0.0001

i used Z-table that is cumulative from mean. In other words, area between mean = 0 and z.

z = (10 - 3)/1.8 = 3.89

looking at the table, 3.89 corresponds to area of 0.4999

p(t > 10) = 1 - 0.5 - 0.4999 = 0.0001

you can also get the same result from z-table that is cumulative between negative infinity to z

but here

answer = 1 - (table result)

z = 3.89 corresponds to area of 0.9999

p(t > 10) = 1 - 0.9999 = 0.0001

some tables gives you more digits after the decimal points for more precision but to round your answer to 4 decimal places, they give same answer