100-80=20
95-20=75
75+1=76
the answer is 76 dunno if that's how you're supposed to get the answer but I checked it so :/
edit I did the wrong calculations, but I got the right answer
<em>Since we are given with the three sides of the triangle and asked to determine the angle, we can use the cosine law.</em>
<em> b² = a² + c² - 2ac(cosB)</em>
<em>Substituting the known values,</em>
<em> (1.8)² = (2.4)² + (1.6)² - 2(2.4)(1.6)(cosB)</em>
<em>The value of B from the equation is 48.6°. </em>
<u>Answer:</u>
- The first four terms are <u>4</u><u>,</u><u>8</u><u>,</u><u>1</u><u>2</u><u>,</u><u>1</u><u>6</u>
<u>Step-by-Step </u><u>Explanation</u><u>:</u>
The given relation between the nth term and it's previous term is given by:

GiveN:
Now finding the other three terms of the AP with the given relation.

Putting a1 = 4,

Now, Third term:

Putting a2 = 8,

Now, Fourth term:

Putting a3 = 12,

Hence, The first four terms of the AP is 4, 8, 12 & 16.
Slope as an (improper fraction)-9/7, it can’t be simplified