1. **Problem Statement:** We have a parallelogram with one side length of 70 mm and the adjacent side length labeled as $t$. The perimeter of the parallelogram is given as 149.2 mm. We need to find the value of $t$. 2. **Formula for Perimeter of a Parallelogram:** The perimeter $P$ of a parallelogram is given by the formula: $$P = 2(a + b)$$ where $a$ and $b$ are the lengths of adjacent sides. 3. **Apply the formula:** Here, $a = 70$ mm and $b = t$ mm. Substitute these into the formula: $$149.2 = 2(70 + t)$$ 4. **Solve for $t$:** Divide both sides by 2: $$\frac{149.2}{2} = 70 + t$$ $$74.6 = 70 + t$$ Subtract 70 from both sides: $$74.6 - 70 = t$$ $$t = 4.6$$ 5. **Answer:** The value of $t$ is 4.6 millimeters.