To convert $-40^\circ 36'$ into decimal degree notation:

1. The degrees part is $-40^\circ$.
2. The minutes part is $36'$. There are 60 minutes in a degree, so we convert the minutes to decimal degrees by dividing by 60:

$\frac{36}{60} = 0.6$

3. Combine the degrees and the converted minutes:

$-40 + (-0.6) = -40.6^\circ$

Thus, $-40^\circ 36'$ in decimal degree notation is $-40.6^\circ$.

Would you like more details or have any questions?

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Here are 5 related questions for further practice:

1. How do you convert 25° 45' into decimal degrees?
2. What is 10° 15' into decimal degrees?
3. How do you convert decimal degrees back into degrees, minutes, and seconds?
4. What is the decimal degree conversion of -80° 30'?
5. How can you convert 5° 50' 30" into decimal degrees?

Tip: When converting minutes to decimal degrees, always remember that there are 60 minutes in a degree. Divide the minutes by 60 to find the decimal equivalent.