Let the amount of GST be Rs. x.
Price of walky talky with GST = Rs. 84,000
Taxable value of walky talky = Rs. (84,000 – x)
Now, GST = 12% of taxable value

∴ Amount of state and central GST charged by the dealer is Rs. 4,500 each. Taxable value of the set is Rs. 75,000.
∴ Amount of state and central GST charged by the dealer is ₹ 4,500 each. Taxable value of the set is ₹ 75,000