Let’s set up an equation by calling the lifespan of a bat x, and therefore the lifespan of the hamster x – 6, and the lifespan of the frog 4 (x – 6) which add together to equal 30, like this: x + x – 6 + 4 (x – 6) = 30.
That gives us 6x – 30 = 30 and we should add 30 to each side to try to isolate the x.
Now we have 6x = 60, which we will divide by 6, 6x / 6 = 60 / 6.
This gives us x = <<10=10>>10. The bat has a lifespan of 10 years.
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