I like the 'question mark' at the end:
26 letters (English), 10 digits (0,1,...9)
26*26*10*10*10 = 676000
Now, this was for LLDDD (Letter Letter Digit Digit Digit)
It seems this is the order they want. Other wise, one should multiply by all the combinations in the order: LDLDD, DLLDD, etc ... (10 combinations), but again it seems they want this LLDDD
So 676000
Answer:
The concentration is simply 36%
Step-by-step explanation:
In this question, we are concerned with calculating the concentration of a new mixture formed from mixing some liters of each of two vinegar variants of different concentrations.
We proceed as follows;
The concentration of the new solution will contain 12% of 13L vinegar A and 70% of 9L vinegar B
13L of vinegar A will contain 13 * 12% = 13 * 0.12 = 1.56
9L of 70% vinegar B will contain 9 * 70% = 9 * 0.7 = 6.3
Now, the new mixture has a total volume of 13 + 9 = 22L
The concentration of the new mixture will thus be;
(1.56 + 6.3)/22
= 0.357 and that’s approximately 0.36 or simply 36%