Assume Cost of TV and Washing Machine

Let the cost of 1 TV be $100$. Since the cost of a washing machine is 75% less than the TV, the cost of 1 washing machine is $100 - 75 = 25$.

$T = 100, \quad W = 25$

Calculate Initial Total Cost

We need the total cost of 8 washing machines and 2 TVs. Using our assumed values: Initial Cost = $8 \times 25 + 2 \times 100 = 200 + 200 = 400$.

$\text{Initial Total} = 8(25) + 2(100) = 400$

Calculate New Costs after Percentage Changes

The washing machine cost increases by 77%: New $W = 25 \times 1.77 = 44.25$. The TV cost decreases by 27%: New $T = 100 \times 0.73 = 73$.

$W_{new} = 44.25, \quad T_{new} = 73$

Calculate New Total Cost

Compute the new total cost for 8 washing machines and 2 TVs: New Total = $8 \times 44.25 + 2 \times 73 = 354 + 146 = 500$.

$\text{New Total} = 8(44.25) + 2(73) = 500$

Determine Net Percentage Change

The change in total cost is $500 - 400 = 100$. The percentage change is $\frac{100}{400} \times 100\% = 25\%$.

$\text{Percentage Change} = \frac{500 - 400}{400} \times 100\% = +25\%$