Answer:
140 individuals were surveyed
42 people are planning on going to the mountains
Step-by-step explanation:
The question is missing the information regarding the percentage of people who said that they were going to each of the possible destinations. After a quick google search I've found that, in the original question, 32% of individuals were going to the beach, 15% to the desert, 23% to major cities, and 30% to the mountains.
If 21 people said they were going to the desert, and that corresponds to 15% of the total number of people surveyed, the number of people surveyed is:
140 individuals were surveyed
Since 30% responded "the mountains", the number of people planning on going to the mountains is:
42 people are planning on going to the mountains