EXPLANATION
Let's see the facts:
People with reptils = 160 {40% pet snakes,}
From 40% pet snakes -------> pet lizard
Those who don't have a pet snake----> 75% pet lizard.
Let's make the table:
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Has snake----> 40% = 0.4 in decimal form
Multiplying this by the number of people with reptils:
160*0.4 = 64
No snake ------> (100% - 40%) = 60% = 0.6 in decimal form
Multiplying this by the number of people with reptils:
160*0.6 = 96
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Has snake:
Has lizard+snake ----> 25% = 0.25 in decimal form
Multiplying this by the number of people with snake:
64*0.25 = 16
No lizard, just snake---> (100% - 25%) = 75% = 0.75 in decimal form
Multiplying this by the number of people with snake:
64*0.75 = 48
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No snake:
Has lizard ----> 75% = 0.75 in decimal form
Multiplying this by the number of people without snake:
96*0.75 = 72
No lizard and no snake---> (100% - 75%) = 25% = 0.25 in decimal form
Multiplying this by the number of people with snake:
96*0.25 = 24
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The table will be:
Has lizard No lizard Total
Has Snake 16 48 64
No snake 72 24 96
Total 88 72 160