How do i solve 1.451 = 1.470 - Ri * 0-0148
What is Ri ? Is that 2 things or just one?
Is that hyphen between the 2 zeros meant to be a decimal point?
anyway
$$\\1.451 = 1.470 - Ri * 0.0148 \\1.451-1.470 = - Ri * 0.0148 \\-0.019 = - Ri * 0.0148 \\Ri=0.019/0.0148$$
and you can finish it