Let she deposit ₹ x in the 1st bank at the rate of 6% and Rs (10000-x) in the 2nd bank at the rate of 7 % for 2 years
According to the problem,
₹ {\frac{x × 6 × 2}{100}+\frac{(10000-x) × 7 × 2}{100}} = ₹ 1280
or, \frac{12x}{100}+\frac{14(10000-x)}{100} = 1280
or, frac{12x+140000-14 x}{100} = 1280
or, -2x + 140000 = 1280 × 100
or, 140000 – 128000 = 2x
∴ x = =\frac{12000}{2}=6000
∴ She deposited ₹ 6000 in the 1st bank & ₹ 4000 in the 2nd bank.