Quarters weigh 6 grams while dimes weigh 2 grams. Quarters weigh $6$ grams while dimes weigh $2$ grams. Tiffany has $\$5.35$ worth of quarters and dimes in her pocket weighing a total of $124$ grams. How many **quarters** does Tiffany have?

Let us call $Q$ the number of quarters and $D$ the number of dimes. So, the amount of money (in cents) gives $$25 Q+ 10 D=535$$ For the weight $$6Q+2D=124$$ So, two equations for two unknowns.

I am sure that you can take from here.