Elmer has a collection of 300 fossils. Of these, 21 percent are fossilized snail shells. How many fossilized snail shells does Elmer have?

Answer 1

The way this problem is worded may make it harder to come up with an equation for it, but the equation should be:

fossilized snail shells = 21% of collection

x = .21 * 300

x = 63

So Elmer has 63 fossilized snail shells.

Answer 2

This question is a basic percent problem - What is 21% of 300. Remember that you can't calculate with a percent, you have to use its fractional or decimal equivalent. In this case 21% doesn't lend itself to a fraction, so change to a decimal by multiplying by 0.01- that's the same as moving the decimal point two places to the left. 21% x 0.01 = 0.21. Now 0.21 x 300 will give the no. of fossilized snail shells.

To avoid the need to convert, you can use the proportion method that automatically converts the pct. to a fraction.

Pct/100 = Amt/Base Here, we know the pct. and the base and need to solve for the amount.

21/100 = x/300. As with any proportion, cross-multiply to convert to a "single-layer" equation.

100x = 6300 and solve for x by dividing both sides by 100 (same as moving dec pt two places to left) Should give same answer as above method.