So, here you have to look at the periodic table and see what the molar mass of each molecule composing the water compound

its two hydrogen atom plus an oxygen molecule, making it about 18g per mol.
That said, looking at the mass, we have to ask ourselves, if a mol of water contains 18g of mass, how many moles do we have in 0.5g of water?
We just do a cross multiplication:
Answer:
Step-by-step explanation:
so add what you have if you one number spilt it and divide
We know that Bob and Caitlyn are playing a trading-card game. Between them, they have 81 cards. <span>Bob has 7 fewer cards than Caitlyn. Since Bob has 7 cards fewer them Caitlyn we have to divide by 2 and subtract 7.
81 / 2 = 40 [rounded]
40 - 7 = cards Bob has
= 33 cards bob has
</span>
Answer:
the previous population was 62,000.
Step-by-step explanation:
The current population of a city = 83,700
The population of a city has increased by 35% since it was last measured.
We have to calculate the previous population before increasing 35%.
Let the previous population be p
p +(35% × p) = 83,700
p + 0.35p = 83,700
1.35p = 83,700
p =
p = 62,000
Therefore, the previous population was 62,000.
Step-by-step explanation:
n-8≤17
add 8 on both sides to isolate the variable.
n is less than or equal to 25