Question

390 + 4 900: k= 460
230 a + 40 = 10 000:20
помогитеее пж​

Answer 1

$390 + 4900 \div k = 460 \\ 4900 \div k = 460 - 390 \\ 4900 \div k = 70 \\ \frac{4900}{k} = \frac{70}{1} \\ 70k = 4900 \\ k = 4900 \div 70 \\ k = 70$

$230a + 40 = 10000 \div 20 \\ 230a + 40 = 500 \\ 230a = 500 - 40 \\ 230a = 460 \\ a = 460 \div 230 \\ a = 2$