Answer:
C) 21 girls : 9 boys
Step-by-step explanation:
You just have to compare the ratio you're given to the answers and see if the ratios from the answers match up to the ratio you were given. The reason C is the answer is because if you divide by 3 in the ration, it is the same as the ratio you were given, 7:3
Answer:

Step-by-step explanation:

Answer:
Step-by-step explanation:
1. 3.8 x 10^5 + 5.5 x 10^5 = 930,000 or 9.3 x 10^5
You just have to solve the equation and shorten the answer. For number one the answer is 930,000, so you have to make it into a number with decimals since a scientific notation number can not be equal to 10 or be greater. So you have to round the number to 9.3 not 93. To "round" it to 9.3 you have to move the decimal at the end of 930,000 to be in between the numbers 9 and 3. How many times you move the decimal to the left or right, that is the exponent of 10. So for 930,000 you moved the decimal 5 times to the left so the exponent for 10 is positive 5.
Answer:
C, 40%
Step-by-step explanation:
0.15 + 0.25 is 0.4 and in percentage that is 40%
Turn both fractions into mixed fractions resulting in 75/2 and 5/2. Then turn them into decimals. 75/2= 37.5 and 5/2= 2.5. Then divide each other 37.5 / 2.5= 15. 15 is your answer. Hope it helped :)