After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight (in pounds)?

Step-by-step explanation:

From the problem we know that 12% of Lisa's original weight is 21 pounds. Let's call Lisa's original weight x and rewrite what we know from the question in terms of x.

We can convert 12% into a decimal - 0.12. We can also recognize that the word "of" used in a word problem often means you need to multiply. So, we can multiply 0.12 by x because we know 12% of Lisa's original weight.

0.12x = 21

To solve this equation, we need to isolate x, so we can divide both sides by 0.12.

x = 175. ==> Lisa's original weight was 175 pounds.

If you don't have a calculator or would like to learn another way to solve this problem, you can use proportions.

We know that 12% of x is 12, so what is 100% of x? (this is another way to rewrite the question)

We can contine to rewrite this by writing

We can write this because we know that the ration of 12% to 21 pounds is going to be the same ratio of 100% to Lisa's entire body weight.

We can multiple by both sides of the equation by  , which is equal to 1 so it won't change the value of the equation, to remove the denominators. Then, we'll end up with:

12x = 100*21

12x = 2100

x = 175

plants store their excess carbohydrate in the form of starch so that it could be used as energy source later on. the excess carbohydrate is converted into starch in the plastid i.e. chloroplast & this process occurs in the presence of sunlight. it is an insoluble polymer of glucose which gets stored in cell organelles named as amyloplasts. in some plants, starch is also stored in roots and embryos.