A brief solution at the Tribinnov Africa Assessment test question.

tribinnov.js

/**
 * Collects inputs in percentages, for example: COOP(30, 20, 10, 15, 25) means 30%, 20%, 10%, 15%, and 25% respectively.
 * 
*/
function COOP (loan, convertibleNote, grants, equity, sharedProfits, baseAmount = 5000) {
  const args = [ ...arguments ];
  if(args.length < 5) throw new Error("Must provide percentages for all sub-wallets");
  
  if(baseAmount !== 5000) {
    throw new Error("Invalid Base Amount. Ensure it is 5000.");
  }
  if(args.find(arg => arg > 50)) {
    throw new Error("Sub-wallet percentage cannot be more than 50%.");
  }
  const totalPercentages = args.reduce((acc, curr) => acc += curr, 0);

  if(totalPercentages > 100) {
    throw new Error("Sum of percentages must not be more than 100.");
  }
  if(totalPercentages !== 100) throw new Error("Sum of all inputed percentages must be 100.");
  
  const actualValues = args.map(arg => arg / 100 * baseAmount);
  
  return {
    loan: actualValues[0],
    convertibleNote: actualValues[1],
    grants: actualValues[2],
    equity: actualValues[3],
    sharedProfits: actualValues[4]
  }
}



//console.log(COOP(10, 20, 30, 20, 20));
//COOP(45, 16, 50);