Secret family recipe for cookies

1. Set up an equation. : $\frac{30}{4}$ = $\frac{75}{x}$

2. Solve for x

3. Cross multiply : 30x = 4(75)

4. Simplify : 30x = 300

5. Isolate x : $\frac{30x}{30}$ = $\frac{300}{30}$

6. Simplify again : x = 10

this problem is example of direct proportion assumption : x is teaspons for make 75 cookies so we can write : 30 cookies => 4 teaspons 75 cookies => x teaspons use cross time so 30x= 75.4 x= 75.4/30=10

We know that 30 cookies is to 4 teaspoons of baking soda.

So

30:4 as 75:x

To solve for x,

30x= 75(4)

x = 10

30 cookies = 4 teaspoon

75 cookies = ? teaspoon

? = 75 x 4 / 30

? = 300 / 30

? = 10 teaspoon

30/4 = 75/X

75*4 = 30X 300=30X

X=10

30 cookies = 4 teaspoons of baking soda 1 teaspoons of baking soda = 7.5 cookies 75 cookies/7,5 cookies = 10 teaspoons of baking soda many teaspoons of baking soda does he need = 10 teaspoons of baking soda

30 (cookies) >>needs>> 4 (baking soda) > 75 (cookies) >>needs>> X (baking soda) >>> X = ( 4 * 75 ) / 30 = 10

Baking Soda required for 30 cookies = 4 teaspoons. Baking Soda required for 1 cookie = 4/30 teaspoons. Baking Soda required for 75 cookies = (4/30)*75 =10 teaspoons

by using unitary method we get 4-30 ?-75 we get 75*4/30=10

Firstly see the relationship between the cookies, 30 and 75. So divide 75 by 30, and you get 2.5. Because it takes 4 teaspoons of baking sugar to make 30 cookies, we can times 4 by 2.5, and we have the answer, 10.