Question

please solve the 7 question

Answer 1

use oppo . best for taking photo ok ..........

Answer 2

$1st \: case \\ \\ \\ simple \: interest = \frac{prt}{100} \\ = \frac{400 \times r \times 2 }{100} = 8r \\ \\ \\ \\ 2nd \: case \\ interest = \frac{550 \times r \times 4}{100} = 22r \\ \\ \\ 3rd \: case \\ \\ interest = \frac{1200 \times r \times 6}{100} = 72r \\ \\ \\ 8r + 22r + 72r = 1020 \\ 102r = 1020 \\ r = 10$
rate of interest=10% per annum