Answer:
I believe it's 36
Step-by-step explanation:
Also is this a test lol?
well, rational = fractional, namely something you can write as a fraction, well, anything between -1 and -2 is just less than -1 so

* means multiply, sqrt=radical
expand
-10+sqrt2*8i-sqrt2*15+24i
group
(-10-sqrt2*15)+(sqrt2*8+24)i
not exactly sure though
Took 3 of us in grade 10 but johns present age is 77.5 and his sister is 72.5