Respuesta :

0.8+0.3m+0.6-0.5m = 0.4

or, 1.4-0.2m=0.4

or, -0.2m = 0.4 - 1.4

or, -0.2m = -1

or, m = -1/-0.2 = 10/2 = 5

The answer is 5.

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