Apopulation of snails exhibits two morphotypes - (i) dominant dark color [dd and dd], and (ii) recessive light color [dd]. you observe in a population produces 25% homozygous dominant, 43% heterozygous, and 32% homozygous recessive. if there were 100 individuals in the population, how many dominant alleles are present in the entire population?

To solve this question you need to understand how dominant and recessive allele works. When an organism has both dominant and recessive allele(called heterozygote), the organism will express only the dominant allele.  The question asked for dominant allele in the entire population. That means it was the homozygous dominant and the heterozygote. The number would be: (25%+43%) * 100= 68 individual

If the question asked for the fraction of allele it would be:
25%*100 individual *2 allele/individual + 43%*100 individual* 1 allele/individual= 50+43=93 allele

The answer would be sand and gravel