1. Problem 1: The total cost of a tablet device is divided into material, labour, and overheads in the ratio 3:4:1. The cost of material is given as 315. We need to find the total cost of the tablet. 2. Formula: If the ratio parts are $a:b:c$ and one part's cost is known, the total cost is given by: $$\text{Total cost} = \text{Cost of one part} \times \frac{a+b+c}{\text{part ratio of known cost}}$$ 3. Applying the formula: Material ratio = 3, Labour ratio = 4, Overheads ratio = 1 Total ratio = $3 + 4 + 1 = 8$ Material cost = 315 corresponds to ratio 3 4. Calculate the cost of one ratio part: $$\text{Cost per part} = \frac{315}{3} = 105$$ 5. Calculate total cost: $$\text{Total cost} = 105 \times 8 = 840$$ 6. Answer for Problem 1: The total cost of the tablet is 840. --- 7. Problem 2: In the triangle, find the value of $y$ given angles $40^\circ$, $x^\circ$ inside the triangle, and an exterior angle $3x^\circ$ adjacent to $x^\circ$. 8. Important rule: The exterior angle of a triangle equals the sum of the two opposite interior angles. 9. Using the exterior angle property: $$3x = 40 + y$$ 10. Also, the sum of angles in a triangle is 180 degrees: $$40 + x + y = 180$$ 11. From the exterior angle equation: $$y = 3x - 40$$ 12. Substitute $y$ into the triangle sum equation: $$40 + x + (3x - 40) = 180$$ Simplify: $$40 + x + 3x - 40 = 180$$ $$4x = 180$$ $$x = 45$$ 13. Find $y$: $$y = 3(45) - 40 = 135 - 40 = 95$$ 14. Answer for Problem 2: The value of $y$ is 95.