Grandpa has twenty-four coins in his pocket. grandpa gives sam some clues about the total value of the coins in his pocket :

one-sixth of the coins aré quarters
one- half of the coins aré dimes

grandpa has the equal amount of nickels and pennies grandpa says sam can have all the coins he has in his pocket if he discovers the correct total value of the coins. what is the total value of the coins in grandpas pocket that sam should discover? show all your mathematical thinking

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?