how to display in the selected currency input placeholder a value of 1?

i'm trying to display a value of 1 in the placeholder of my input when i select a currency, but instead of 1 i see the exchange rate of the selected currency with USD, for example if i select EUR instead of 1 i see 0.93 (1 USD = 0.93 EUR). Any suggestion how to fix it? The issue is only in the placeholder of the currency that i've choose, in the second input box i see the correct exchange rate between the selected currency and the other currency.

     let selectedCurrency1 = "USD";  let selectedCurrency2 = "EUR";  let exchangeRate: number;  function handleSelectChange(event: any, currency: any) {    if (currency === 1) {      selectedCurrency1 = event.target.value;      if (input1) {        input1.placeholder = "1";      }    } else if (currency === 2) {      selectedCurrency2 = event.target.value;      if (input2) {        input2.placeholder = "1";      }    }    updateExchangeRate();  }  function updateExchangeRate() {    const rate1 = exchangeRates[selectedCurrency1];    const rate2 = exchangeRates[selectedCurrency2];    const exchangeRate = rate2 / rate1;    const input1 = document.getElementById("rate1") as HTMLInputElement;    const input2 = document.getElementById("rate2") as HTMLInputElement;    if (input1 && input2 && exchangeRate) {      input1.placeholder = `${(1 / exchangeRate).toFixed(3)}`;      input2.placeholder = `${(1 * exchangeRate).toFixed(3)}`;    }  }

and this is the block with the input

{#each Object.entries(exchangeRates) as [key, value], index}  {#if index === 0}<div class="input-box"><input type="number" min="0" id="rate1" placeholder={exchangeRates[selectedCurrency1]}/><select id="option1" on:change={(event) => handleSelectChange(event, 1)}>        {#each Object.entries(exchangeRates) as [key, value]}          {#if key === selectedCurrency1}<option value={key} selected>{key}</option>          {:else}<option value={key}>{key}</option>          {/if}        {/each}</select></div>  {/if}{/each}