BODMAS stands for, Bracket Orders(powers, exponent) Divisional Multiplication Addition Subtraction. Question are solved in that order.
Given,
500×3+6÷−4
First we solve Division
500×3+(6÷6)−4
500×3+1−4
Now, we solve Multiplication
(500×3)+1−4
1500+1−4
Now, we solve addition
(1500+1)−4
1501−4
Now, Subtraction
1497
=1497