2-2:42*70

To solve the expression \(2 - 2:42 \times 70\), we first need to interpret the notation correctly. If we assume that \(2:42\) means \(2\) divided by \(42\), we can proceed with the calculation.

1. Calculate \(2 \div 42\): \[ 2 \div 42 = \frac{2}{42} = \frac{1}{21} \approx 0.0476 \]

2. Now multiply this result by \(70\): \[ \frac{1}{21} \times 70 = \frac{70}{21} \approx 3.3333 \]

3. Finally, subtract this result from \(2\): \[ 2 - 3.3333 \approx -1.3333 \]

So, the calculated value of \(2 - 2:42 \times 70\) is approximately \(-1.3333\). If you meant something else by \(2:42\), please clarify!