Answer:
Step-by-step explanation:

There are 3 odd primes, namely : 3, 5, 7
The total amount of blocks is 9
The odds of picking and odd prime is 
We are given the retail price of desk as $320. The store takes 50% off of the retail price of desk, then its price would become half of the original.
So its new price would be $160.
Now it says that it takes an additional 20% off of all furniture on store's holiday sale. So we need to cut off 20% from new price $160.
Holiday discount = 20% of $160 = 0.2 × 160 = 32.
Final selling price would be = $160 - $32 = $128.
So $128 is the final answer.
Eight more than six times a number added to one more than nine times the number
(8 + 6x) + (1 + 9x)
9 + 15x