Simplify

To simplify this expression, we can combine like terms.

The first term, (12a/5 - 6a - 10a/3), can be simplified by finding a common denominator. The common denominator is 15, so we can rewrite the expression as:

(12a/5 - 30a/5 - 50a/15)

Combining the numerators, we get:

(12a - 30a - 50a)/15

Simplifying the numerator, we have:

(-68a)/15

Now let's simplify the second term, (10a - 2a/5 - 14a/4).

The first term, 10a, remains as is. For the rest of the term, we need to find a common denominator. The common denominator here is 20, so we can rewrite the expression as:

(10a - 4a/20 - 35a/20)

Combining the numerators, we get:

(10a - 39a/20)

Simplifying the numerator, we have:

(-29a/20)

Now we can rewrite the entire expression in standard form:

(-68a/15) - (-29a/20)

To subtract fractions, we need a common denominator. In this case, we can use 60 as the common denominator:

((-68a*4)/60) - ((-29a*3)/60)

Simplifying the numerators, we have:

(-272a/60) + (87a/60)

Combining the numerators, we get:

(-272a + 87a)/60

Simplifying the numerator, we have:

(-185a)/60

The final answer, in standard form, is:

-185a/60