100/100 решение на задача  trekkingMania в judge 

  for-цикъл упражнение , programming basics with javascript 

function trekkingMania(input) {

  let groupNumber = Number(input[0]);

 

  let musala = 0;

  let montblanc = 0;

  let kilimanjaro = 0;

  let K2 = 0;

  let everest = 0;

 

  for (let i = 1; i <= groupNumber; i++) {

    let alpinists = Number(input[i]);

    if (alpinists <= 5) {

      musala += alpinists;

    } else if (alpinists <= 12) {

      montblanc += alpinists;

    } else if (alpinists <= 25) {

      kilimanjaro += alpinists;

    } else if (alpinists <= 40) {

      K2 += alpinists;

    } else {

      everest += alpinists;

    }

  }

  let allAlpinists = musala + montblanc + kilimanjaro + K2 + everest;

  let percentMusala = (musala / allAlpinists) * 100;

  let percentMontblanc = (montblanc / allAlpinists) * 100;

  let percentKilimanjaro = (kilimanjaro / allAlpinists) * 100;

  let percentK2 = (K2 / allAlpinists) * 100;

  let percentEverest = (everest / allAlpinists) * 100;

  console.log(`${percentMusala.toFixed(2)}%`);

  console.log(`${percentMontblanc.toFixed(2)}%`);

  console.log(`${percentKilimanjaro.toFixed(2)}%`);

  console.log(`${percentK2.toFixed(2)}%`);

  console.log(`${percentEverest.toFixed(2)}%`);

}